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Students can Download Chapter 2 Sexual Reproduction in Flowering Plants Questions and Answers, Plus Two Botany Chapter Wise Questions and Answers helps you to revise the complete Kerala State Syllabus and score more marks in your examinations.

Kerala Plus Two Botany Chapter Wise Questions and Answers Chapter 2 Sexual Reproduction in Flowering Plants

Plus Two Botany Sexual Reproduction in Flowering Plants One Mark Questions and Answers

Question 1.
Types of pollination in Commelina is
(a) chasmogamy
(b) geitonogamy
(c) xenogamy
(d) cleistogamy
Answer:
(d) cleistogamy

Question 2.
When pollen is transferred from another of a flower to stigma of the another flower of the of the same plant, it is referred to as
(a) allogamy
(b) xenogamy
(c) geitonogamy
(d) autogamy
Answer:
(c) geitonogamy

Question 3.
For plant breeding purposes: Pollens are stored at -196°C. What is the purpose behind it?
Answer:
Stored pollens can be used as pollen banks in crop breeding programmes.

Question 4.
Pollen tube enters the embryo sac through
(a) Integument
(b) Micropyle
(c) Calaza
(d) Funicle
Answer:
(b) Micropyle

Question 5.
In flowering plants, fertilization occur in
(a) Ovary
(b) Embryo sac
(c) Nucellus
(d) Ovule
Answer:
(b) Embryo sac

Question 6.
The source of food for developing embryo is
(a) Nucellus
(b) Ovule
(c) Endosperm
(d) Anther
Answer:
(c) Endosperm

Question 7.
Out of megaspre tetrad, the functional megaspore is
(a) Any megaspore
(b) Middle megaspore
(c) Micropylar megaspore
(d) Chalazal megaspre
Answer:
(d) Chalazal megaspre

Question 8.
How many megaspore mothe cell are produced in a nuclellus
(a) 3
(b) 1
(c) 2
(d) 4
Answer:
(b) 1

Question 9.
During the development of monosporic development of embryo sac, the nucleus of the functional megaspore divides
(a) Two times
(b) Three times
(c) Onetime
(d) Repeatedly
Answer:
(b) Three times

Question 10.
Cross pollination has an advantage of
(a) Mutation
(b) polyploidy formation
(c) Genetic recombination
(d) Crossing over
Answer:
(c) Genetic recombination

Question 11.
Unisexual flowers prevent
(a) Pollination
(b) Breeding
(c) Self-pollination
(d) Cross fertilization
Answer:
(c) Self-pollination

Question 12.
The function of the filiform apparatus is
(a) To nourish the pollen grain
(b) To guide the entry of pollen tube
(c) To develop pollen tube
(d) To carry pollen tube through style
Answer:
(b) To guide the entry of pollen tube

Question 13.
Find the odd one. Hilum, Funicle, Intine, Integuments
Answer:
Intine

Question 14.
Choose the correctly matched pair.
(a) Coleorrhiza – Hollow foliar structure
(b) Perisperm- Remanents of nucellus
(c) Proembryo – mature embryo
Answer:
(b) Perisperm – Remanents of nucellus

Question 15.
Choose the correct answer. The layer of microsporangium that nourishes the developing pollen grains is
(a) Endothecium
(b) Tapetum
(c) Middle layer
(d) Epidermis
Answer:
(b) Tapetum

Question 16.
A typical angiosperm embryo sac at maturity is.
(a) 7 nucleate 8 celled
(b) 8 nucleate 8 celled
(c) 7 nucleate 7 celled
(d) 8 nucleate 7 celled
Answer:
(d) 8 nucleate 7 celled

Question 17.
The process of formation of fruits without fertilization is called.
(a) Parthenogenesis
(b) Parthenocarpy
(c) Apomixis
(d) Autogamy
Answer:
(b) Parthenocarpy

Question 18.
Identify the wrong statements regarding post – fertilization development.
(a) The ovary wall develops into pericarp
(b) The outer integument of ovule develops into tegmen
(c) The fusion nucleus (triple nucleus) develops into endosperm
(d) The ovule develops into seed
Answer:
(b) The outer integument of ovule develops into tegmen

Question 19.
Dicot emdryo consists of
(a) radicle and plumule
(b) radicle;plumule, cotyledons and sometimes endosperm
(c) radicle and plumule, cotyledons and tegmen
(d) radicle andplumule, cotyledons tegmentesta
Answer:
(b) radicle,plumule, cotyledons and sometimes endosperm

Question 20.
These process are necessary for the complete development of male gametophyte from pollen mother cell
(a) one meiotic and two mitotic divisions
(b) one meiotic cell division and one meiotic cell division
(c) two meiotic cell division and one mitotic cell division
(d) two meiotic cell division
Answer:
(a) one meiotic and two mitotic divisions

Question 21.
A bilobeddithecus anther has 100 microspore mother cells per micro sporangium. How many male gametophytes this anther can produce?
Answer:
400 male gametophytes

Question 22.
An anther with malfunctioning tapetum often failsto produce viable male gametophytes. Give one reason.
Answer:
Tapetum nourishes developing pollen grains

Plus Two Botany Sexual Reproduction in Flowering Plants Two Mark Questions and Answers

Question 1.
Pollen grains are well preserved as fossil for many years due to some characteristics

1. Name the chemical substance present in pollen wall promote such preservation
2. Give reasons.

Answer:

1. sporopollenin
2. It is the most resistant organic material and can withstand high temperatures, strong acids, and alkali. No enzymes can degrade sporopollenin.

Question 2.
One time fertilization is the characteristic feature of majority of plants but angiosperm show two times of fertilization

1. Two fusion occurs are different. Name it and write down the number of nuclei involved in such process
2. Name the products and ploidy.

Answer:

1. Syngamy. Two nuclei Triple fusion, three nuclei
2. Zygote (2n), PEN (3n)

Question 3.
Commelina, viola, and oxalis that carries both chasmogamous and Cliestogamy flowers.

1. Find out the main differences between them.
2. Give the significance of Cliestogamy.

Answer:

1. Chasmogamous flowers with exposed anthers and stigma. Cleistogamous flowers do not open at all.

2. significance of Cliestogamy:

• It ensures self pollination.
• Purity of characters is maintained.

Question 4.

1. Geitonogamy is a functional cross-pollination but not genetically. Justify?
2. In Papaya, Autogamy and Geitonogamy do not occur. Give reason.

Answer:
1. Geitonogamy is functionally cross-pollination because transfer pollen takesplace between different flowers of same plant that bear same genetic makeup.

2. Papaya is dioecios plants, because, the male and female flowers are present on different plants, which prevent autogamy and geitonogamy.

Question 5.
Wind pollination is common in grasses and water pollination in vallisneria. Give the features of these plants to facilitate pollination.
Answer:
1. Grasses

• Pollen grains are light weight and non-sticky
• Stigama is feathery.

2. Vallisneria

• Flowers do not produce nector and fragrance.
• Female flowers reach the surface of water by long stalk.

Question 6.
In most plants continuous self pollination leads to inbreeding depression while in others certain devices that help to discourage self pollination. Give any four devices.
Answer:

1. Pollen release and stigma receptivity are not at the same time.
2. Another and stigma are placed at different positions.
3. Self-incompatibility.
4. Production of unisexual flowers.

Question 7.
The micropyle remains as a small pore in the seed coat. What is its role?
Answer:
Micropyle facilitates the entry of oxygen and water into the seed during germination.

Question 8.
Draw the diagram of a typical dicot embryo and label the parts like plumule, cotyledons, radicle, and root cap.
Answer:

Question 9.
Observe the developmental stages given below and answer the following.

1. Name the process.
2. Label the stages A, B, C & D

Answer:

1. Embryogenesis (Formation of embryo)
2. A-proembryo B-globular stage C-heart shaped stage D-mature stage

Question 10.
Apomictic seeds are important in agriculture. Do you agree? Give reason.
Answer:
Yes. These seeds are formed without fertilisation hence there is no genetic variation .This feature is helpful to preserve the desirable characters for many years.

Question 11.
Give the technical terms for the following

1. Produce seeds without fertilization
2. Persistent nucellus

Answer:

1. Parthenocarpy
2. Perisperm

Question 12.
Emasculation may not be necessary. Yet bagging is necessary. Justify giving the condition when such a thing can happen.
Answer:
When the flower chosen is unisexual (female), there is no need for emasculation. Yet bagging is necessary to prevent contamination of the stigma with unwanted pollen grains.

Question 13.
Banana is a true fruit and also a parthenocarpic fruit. Justify.
Answer:
Since banana fruit is formed from ovary it is true fruit. It is parthenocarpic because the ovary develops into fruit without fertilization.

Question 14.
Arrange the following terms in the correct development sequence: Pollen grain, sporogenous tissue, microspore tetrad, pollen mother cell
Answer:
Sporogenous tissue → Pollen mother cell → Microspore tetrad → Pollen grain.

Question 15.
Some peoples live in area are subjected to allergic disease due to pollen grains.

1. Give an example for plants that produce pollen of above type?
2. Give an example for two disease?

Answer:

1. Parthenium (Carrot grass)
2. Asthma and Bronchitis

Question 16.
Typical angiosperm embryo sac is 7 celled and 8 nucleate. This condition occurs due to the development of megaspore mother cell

1. How many meiotic and mitotic division takes place
2. What you mean by monosporic development?

Answer:

1. Single meiotic division and 3 mitotic division.
2. Single functional megaspore develops into mature embryo sac.

Question 17.
Pollen allergy that causes chronic respiratory disorders in men like asthma and bronchitis. Name the causative plant.
Answer:
Parthenium or carrot grass

Question 18.
Some pollen grains cannot germinate on stigmatic surface due to the loss of viability

1. Name the factors influence the viability of pollen
2. How do the pollen grains can keep up for many years

Answer:

1. Temperature and humidity
2. Pollen grains are kept in Pollen Bank at-196 degree Celsius in liquid nitrogen.

Question 19.
Pollen tube growth occurs through the stylar region and reach micropyie of ovule. Name the special cellular thickening that guides Pollen tube
Answer:
Filiform apparatus

Question 20.
Pollengrains of many plants are found to be allergic.

1. Do they have any benefits other than the involvement in reproduction? Explain
2. Give examples.

Answer:
1. Pollen grains are rich in nutrients. In recent years pollen tablets are used as food supplements. It is used in western countries in the form of syrup and tablets. Pollen consumption has been claimed to increase the performance of athletes and race horses.

2. Parthenium, acasia

Question 21.
Zygote development leads to the formation of embryo.

1. Name the nutritive tissue that helps in the development of embryo
2. What will be the ploidy of such a tissue

Answer:

1. endosperm
2. endosperm is triploid

Question 22.
Suppose you are given four flowers namely maize, vallisneria, sunflower, and zostera.

1. State the mode of pollination in each flower.
2. Differentiate between cleistogamous and chasmogamous flowers.

Answer:

1. Maize-wind pollination
Vallisnaria-water pollination Sunflower – insect pollination

2. Cliestogamous – closed flower
Chamogamous – opened flower

Question 23.
A close relationship exist between a species of moth and the plant Yucca, where both species moth and Yucca cannot complete their life cycles without each other. Justify it.
Answer:
The moth deposits its eggs in the locule of the ovary of the Yucca flower. Flower in turn gets cross pollinated by the moth. The larvae of the moth come out of the eggs as the seeds starts developing.

Question 24.
Coconut and groundnut are oil yielding crops, point out the difference in the structure of seed.
Answer:
Coconut is an endospermous seed. Reserve food materials like fat, oil, etc. are stored in endosperm, in which the prominent part is endosperm and small sized embryo is situated at one end of the endosperm.

Question 25.
Seeds are formed in angiosperms when male and female gametes get fused. But in some plants seeds are produced without the fusion of gametes.

1. Name the process,
2. Comment.

Answer:
1. Apomixis

2. Apomixis is a form of asexual reproduction which mimics sexual reproduction. Seeds are produced from a diploid egg cell without reduction division and fertilization. Nucellar tissue surrounding the embryosac develops into an embryo.

Question 26.
In market, seedless grapes are high priced than seeded grapes. Give the method used to develop the former.
Answer:
The seedless grapes are developed through induced parthenocarpy.

Question 27.
Plant A with combined desired characters that are inherited from parents. Plant B with desired characters are pure. Find out the types of pollination leads to accurance of characters in both A & B.
Answer:
In plant A, cross-pollination leads to the occurance of mixing of characters while in Plant B self pollination and self-fertilisation results the pure character.

Question 28.
If the diploid chromosome number of a plant is 24. Find out the number of chromosomes in synergid, Antipodal, and endosperm.
Answer:
Here 2n=24, n=12 so the number of chromosomes in synergids and antipodals are 12 each. But endosperm is triploid, chromosome number is 36.

Question 29.
Pollination is aided by biotic and abiotic agents. Identify the type of pollination in Vallisneria, coconut, and grass.
Answer:

• Vallisneria -water pollination
• Coconut and grass-wind pollination.

Question 30.
Give the technical terms for the following

1. Produce seeds without fertilization
2. Persistent nucellus
3. Cotyledons of grass family
4. Protective sheath of radical.

Answer:

1. Parthenocarpy
2. Perisperm
3. Scutellum
4. Coleorhizae

Question 31.
Why do you think the zygote is dormant for some time in a fertilized ovule?
Answer:
This is because the embryo develops only after the formation of endosperm. So the zygote wait for endosperm formation which supplies food material for developing embryo.

Question 32.
In some plants self-pollination is prevented by genetic mechanism of either pollen or pistil

1. Name the process
2. Why does such process not lead to seed formation?

Answer:

1. Self incompatibility
2. It is because of interaction between the chemicals of the pollen and those of stigma (Pollen-pistil interaction)

Question 33.
If one can induce parthenicarpy through the application of growth substances, which fruits would you select to induce parthenocarpy and why?
Answer:
Watermelon, Orange and lemon because in these fruits the seeds are scattered within their edible parts and if seed are removed they become more valuable.

Question 34.
Embryosac or female gametophyte of angiospemn is 7 celled and 8 nucleate How many haploid cells are present in micropylar and chalazal part of female gametophyte of a flowering plant? Name them.
Answer:
Chalazal-Antipodals3, micropylar- Synergids 2, Egg cell 1.

Question 35.
If you squeeze seed of orange you might observe many embryos of different sizes? How is it possible?
Answer:
In orange, nucellar cells surrounding embryosac start dividing, protrude into embryosac and form many embryos.

Question 36.
If the chromosome number of plant species is 16. What would be the chromosome number and ploidy level of

1. microspore mother cell
2. endosperm cells

Answer:

1. Microspore mother cell 16
2. Endosperm cell 24

Question 37.
Observe the flow chart given below. Fill in the blank 1 and 2. Write the relevance of the process indicated as 1.

Answer:

1. Bagging
2. Artificial pollination In bagging the entry of unwanted pollen to stigmatic surface is prevented

Question 38.
Apple and mango are fruits. But they are formed in different ways. How are they formed?
Answer:
Apple is called as false fruit because thalamus develops into fruit. Here ovary is not involved. Mango is a fruit because it is formed from ovary

Question 39.
The synergids have special cellular thickening. Name the thickening and write its function.
Answer:
Filiform apparatus
It guides the pollen tube into the synergid

Question 40.
Analyse the table and fill in the blank.

Answer:

1. Thalamus also contributes to fruit formation
2. True fruit
3. Parthenocarpy
4. Banana

Question 41.

Answer:

1. a – Micropyle
2. b – Embryo sac
3. c – Nucellus
4. d – Chalaza

Question 42.
The embryo sac development in majority of flowering plants is monosporic development. Explain this type of embryo sac development.
Answer:
In this type a single megaspore mother cell of the nucellus differentiates in the ovule. Here Megaspore mother cell undergoes meiosis to form four megaspores, out of four, one megaspore becomes functional, while the other three degenerate. The functional megaspore develops into fully matured embryo sac.

Question 43.
Self incompatibility and dioecious condition are two devices for discouraging self pollination in plants. Explain the two.
Answer:
Self incompatibility – In this, pollen fail to germinate on stigma/pistil of the same flower. This is due genetic mechanism of either male parent or female parent. Dioecious condition – It is the occurrence of Male and female flowers on different plants.

Question 44.
Peculiarities of certain parts of the ovule are given below. Name the parts.

1. Protective envelops of the ovule
2. Stalk of the ovule
3. The layer of cells within the integuments
4. Junction between ovule and funicle

Answer:

1. Integuments
2. Funicle
3. Nucellus
4. Hilum

Question 45.
Geitonogamy and xenogamy are two types of pollination. Differentiate between the two.
Answer:
1. Geitonogamy
It is the transfer of pollen grains from the anther to the stigma of another flower of the same plant.

2. Xenogamy
It is the transfer of pollen grains from anther to the stigma of a different plant.

Question 46.
The inner most wall layer of microsporangium is tapetum. It is multinucleate. Justify this statement.
Answer:
Out of four wall layers of anther, tapetum is the innermost layer that nourishes the developing pollen grains.

Question 47.
Peculiarities of two types of seeds are given below. Identify the two types of seeds and give example for each.

1. Endosperm completely used by embryo.
2. Endosperm not completely used by embryo.

Answer:
1. Non-albuminous/Ex-albuminous
Eg: Pea, Groundunt, etc.

2. Albuminous
Eg: Wheat, Maize, Barley, Castor, etc.

Question 48.
The embryo of monocotyledons and dicotyledons show difference in structure. Explain the structure of dicot embryo.
Answer:
A dicot embryo has an embryonal axis and two cotyledons. The portion of embryonal axis above the level of cotyledons is the epicotyl.it terminates in plumule. The Cylindrical portion below the level of cotyledons is hypocotyl, it terminates at its lower end in radicle.

Question 49.
Occurrence of more than one embryo in a seed is called polyembryony.

1. Give two examples of polyembryony.
2. How does polyembryony occur?

Answer:

1. Citrus and mango
2. Some of the nucellar cells surrounding the embryo sac is diploid that start dividing and develop into the embryos.

Question 50.
Mature pollen grain has a vegetative cell and a generative cell. Write the peculiarities of the two cells.
Answer:
Vegetative cell – It is the bigger cell possess abundant food reserve, Large irregularly shaped nucleus. Generative cell It is the small cell that floats in the cytoplasm of vegetative cell possess dense cytoplasm and a nucleus.

Question 51.
Endosperm develops from the primary endosperm nucleus. Explain the process of endosperm development.
Answer:
The PEN undergoes successive nuclear divisions that give rise to free nuclei later cell wall formation occurs and becomes cellular eg coconut.

Question 52.
Geitonogamy is similar to autogamy. Justify this statement.
Answer:
In geitonogamy pollen grains come from the same plant. Both Autogamy and geitonogamy are come under self pollination.

Question 53.
Apomixis is an asexual form of reproduction,that mimics sexual reproduction. Substantiate this statement.
Answer:
Apomixis is a kind of asexual reproduction in which seeds are produced without fertilization. By retaining the seed habit, it mimics to sexual reproduction.

Question 54.
Observe the relationship between the first two terms and fill in the blanks.

1. Exine: Sporopollenin; Intine : …………..
2. Pistils fused: Syncarpous; Pistils free: ………….
3. Zygote : 2n ; Endosperm : …………..

Answer:

1. Cellulose and pectin
2. Apocarpous
3. 3n

Plus Two Botany Sexual Reproduction in Flowering Plants Three Mark Questions and Answers

Question 1.
Pollen grains in angiosperms ace not motile. They have to be carried to the stigma by external agents.

1. Name the process of transfer of pollen grains.
2. Write the name of three such agents.
3. Explain how it takes place in vallisnaria.

Answer:
1. Transfer of pollen grains from the anther to the stigma is called pollination.

2. Wind water and animals

3. In vallisneria the female flowers reach the surface of water by long stalk and the male flowers or pollen grains are released to the surface of water and are carried by water currents to the female flower and fertilization takes place.

Question 2.
Ramu while observing the C.S. of anther of Datura through a microscope, found fourwall layers.

1. Name the layers.
2. Write down its functions.

Answer:
1. layers:

• epidermis
• endothecium
• middle layer
• tapetum

2. The outer three layers perform protective function. Tapetum nourishes the developing pollen.

Question 3.
In flowering plants microspores are formed by meiosis and are haploid tetrads

1. How will you show the formation of microspores and male gametophyte from microspore mother cells
2. Write down the formation of embryosac and monosporic development?

Answer:
1. In the anther each cell of sporogenous tissue act as microspore mother cells (2n) which undergoes meiosis and forms four microspores (n) which are arranged in a cluster of four cells, ie.

microspore tetrad. When the anther matures the microspore dissociates from each other and develop into pollen grains. The pollen grains represents male gametophyte.

2. The nucellus of the ovule one cell is enlarged and act as megaspore mother cell (2n) which undergoes meiosis and results four megaspores (n) one of the megaspore is functional while the other three degenerates.

Only the functional megaspore develop into the embryo sac. Thus embryo sac formation from a single megaspore is called ‘monosporic’.

Question 4.
Fill up the blanks by observing the first pair.
1. Plumule: Shoot
………….: Root

2. Shoot apex: Coleoptile
Root apex: ………..

3. Ovary: Pericarp
Nucellus: ……………

4. Zygote: Embryo
…………: Endosperm

5. Syngamy: Zygote
……….: PEC

6. Ovule: Seed
…………: Seed coat

Answer:

1. Radicle
2. Coleorhiza
3. Perisperm
4. Primary Endosperm nucleus
5. Triple fusion
6. Integument

Question 5.
Diagrammatic representation of mature embryo sac is given.

1. Identify the cells that are involved in fertilization
2. Write the ploidy condition of that cells before and after fertilization.
3. Point out the role of ‘x’ in the diagram.

Answer:
1. Central cell (with two palar nuclei )and egg

2. Before fertilization – Central cell – 2n/ n+n
After fertilization – Central cell – 3n
Before fertilization – egg – n
After fertilization – egg. 2n.

3. Filiform apparatus – guides the pollen tubes into the synergids at the time of pollen germination prior to fertilization.

Question 6.
Double fertilization is the characteristic feature of angiosperms.

1. What does it mean?
2. Name the products and process.

Answer:1. It is the fertilization takes place two times.
2.

Question 7.
Haploidy, diploidy, and tripoloidy are the ploidy level of angiosperm plant parts from a seed is given below.

1. Find out the chromosome status of each part.

• Integuments outer, inner
• Nucellus
• Secondary nucleus
• Zygote

2. How will you give explanation to reduction of chromosome number from diploid to haploid?

Answer:
1. chromosome status of each part:

• Integuments outer and inner-2n(diploid)
• Nucellus-2n (diploid)
• Secondary nucleus-3n (triploid)
• Zygote-2n (diploid)

2. Chromosome number reduced due to reduction division or meiosis.

Question 8.
A bisexual self pollinating flowering plant has chromosome number 76, in its somatic cells.

1. What will be the chromosome number of its nucellus, synergids, zygote, and endosperm?
2. What is the advantage of cross pollination over self pollination?
3. Give any 2 characteristics of wind pollinated flowers.

Answer:
1. Nucellus is diploid; chromosome no is 76 Synergids are haploid;chromosome no. is 38 Zygoye is diploid; chromosome no. is 76 Endosperm is triploid its chromosome no. is 114.

2. Sexual reproduction brings about genetic recombination and results in the better Survival of the species.

3. The flowers are small and inconspicuous .they are formed in clusters. Lightweight Pollens are produced in large amount. Stigma is long and hairy.

Question 9.
Tender coconut has liquid endosperm inside it. But matured it has only solid endosperm

1. Write down the auction of endosperm.
2. How will you differentiate liquid endosperm from solid endosperm.
3. Name the part of embryo pushes deep into endosperm.

Answer:

1. Provide nutrion.
2. Liquid endosperm- provide nutrition for the development of zygote into mature embryo. Solid endosperm- provide nutrition for the future development of embryo.
3. Suspensor.

Question 10.
60% of angiosperms, pollen grains shed at 2 celled stage, but in some species pollen grains are shed at 3 celled stage.

1. Distinguish between 2 celled and 3 celled stage of pollen grains?
2. Give the significance of germ pore of exine surface

Answer:

1. In 2 celled stage pollen grains contains two cells – bigger vegetative cell and smaller generative cell. In 3 celled stage, pollen grains contains 3 cells vegetative cell and 2 male gametes
2. Germ pore is the opening through which pollen tube come out during pollen germination

Question 11.
In angiosperm 7-celled and 8-nucleate embryosac is formed from single megapore mother cell.

1. Name the process
2. Name the 3 – nuclei found in chalazal part of embryosac
3. Which is the opening of ovule that helps in the entry of pollen tube?

Answer:

1. Megasprogenesis
2. Antipodals
3. Micropyle

Question 12.
Pollen grains in angiosperms are not motile. They have to be carried to the stigma by external agents.

1. Name the process of transfer of pollen grains.
2. Write the name of three such agents.
3. Explain how it takes place in vallisnaria.

Answer:

1. Pollination.
2. Wind, water, and animals
3. In vallisnaria, mature female flower reach the surface of water by the long stalk in the same time male flowers or pollen grains are released on to the surface of water. Stigma collect the pollen grains and come inside the water.

Question 13.
Flowering plants have major devices to discourage self pollination and to increase cross pollination. Point out any four devices.
Answer:
1. Pollen release and stigma receptivity are not synchronised, ie. either the pollen is released before stigma become receptive or stigma becomes receptive much before the release of pollen.

2. In some plants the anther and stigma are placed at different positions so that pollen cannot come in contact with the stigma of the same flower.

3. Self pollination is prevented by self-incompatibility which is a genetic mechanism that prevents the pollen of the same flower or flowers of the same plant from fertilizing the ovules.

4. Production of unisexual flowers also prevents autogamy but not geitonogamy. Dioceous plants prevents both autogamy and geitonogamy.

Question 14.
Maize consists of nectar less flowers but in or chids flowers are nectary and attractive.

1. Distinguish the characteristics of both flowers based on the agents involved in the pollen transfer.
2. Some organisms involved in pollination produce foul odor. Name.

Answer:
1. Maize is a wind pollinated plant. The flowers produce large amount of light and non sticky pollen grains which helps in transportation through wind.

They possess well exposed stamens and large and feathery stigma to easily capture pollen grains. There is a single ovule in an ovary and arranged in compact inflorescence.

Orchid is an insect pollinated plant. It produce large conspicuous flowers, the small flowers are produced in clusters.

The large flowers are colourful, fragrant and rich in nectar. The insects are attracted by colour and fragrance and are often rewarded by nectar and pollen produced by the flower.

2. Flies and beetles.

Question 15.
Wind is an abiotic agent that helps in pollination. Write any six features of wind pollinated flowers.
Answer:

1. Pollen grains are light
2. Non – sticky pollen grains
3. Well exposed stamens
4. Large, feathery stigma
5. Single ovule in each ovary
6. Numerous flowers packed into inflorescence

Question 16.
Observe the figure given below and explain its structure.

Answer:
It is the structure of pollen grain, it has an outer hard layer called exine that possess prominent apertures called germ pores through which pollen tube come out.

The inner wall layer is continuous called intine. Pollen grain has two cells, a large vegetative cell, and a small generative cell.

Question 17.
Observe the diagram given below.

a) Copy the diagram, and label antipodals and synergids.
b) Explain double fertilization.
Answer:
1.

2. At first, one of the male gametes fuses with egg cell to form a diploid zygote. This is called syngamy. The other male gamete fuses with the polar nuclei to form primary endosperm nucleus (PEN). This is called triple fusion. Thus, two types of fusion occur in the embryo sac called Double fertilization.

Plus Two Botany Sexual Reproduction in Flowering Plants NCERT Questions and Answers

Question 1.
Differences between microsporogenesis and megasporogenesis. Which type of cell division occurs during this events? Name the structures formed at the end of these two events.
Answer:

Microsporogenesis	Megasorogenesis
1. It is process of formation of microspores from microspore mother cell. 2. It occurs inside the pollen sacs of anthers.	1.  It is the process of formation of megaspores from megaspore mother cell. 2.  It occurs in nucellus part of ovule.

• In both, the events meiosis cell division occurs.
• Microsporogenesis results in the formation of microspores while megasporogenesis forms megaspores.

Question 2.
Arrange the following terms in the correct development sequence: Pollen grain, sporogenous, microspore tetrad, pollen mother cell, male gametes.
Answer:
Sporogenous tissue ’!Pollen mother cell’!Microspore tetrad’!Pollen grain’!Male garnets.

Question 3.
What is meant by monosporic development of female gametophyte?
Answer:
The formation of female gametophyte or embryo sac from a single functional megaspore is called monosporic. The nucleus of functional megaspore undergoes 3 successive mitotic divisions to form haploid nuclei.

Question 4.
With a neat diagram explain the 7-celled, 8-nucleate nature of the female gametophyte.
Answer:
Embryo sac is an oval multicellular structure which contains 8 nuclei but 7 cells.

Question 5.
What are chasmogamous flowers? Can cross¬pollination occur in cleistogamous flowers? Give reasons for your answer.
Answer:
Chasmogamous flowers have exposed anthers and stigma. Cross pollination cannot occur in cleistogamous flowers, as such flowers do not open at all.

Question 6.
Mention two strategies evolved to prevent self pollination in flowers.
Answer:
Flowering plants have developed many devices to discourage self pollination and to encourage cross pollination.

Plus Two Botany Sexual Reproduction in Flowering Plants Multiple Choice Questions and Answers

Question 1.
Apomictic embryos in Citrus arise from
(a) synergids
(b) maternalsporophytic tissue in ovule
(c) antipodal cells
(d) diploid egg
Answer:
(b) maternalsporophytic tissue in ovule

Question 2.
Wind pollinated flowers are
(a) small, brightly coloured, producing large number of pollen grains
(b) small, producing large number of dry pollen grains
(c) large producing abundant nectar and pollen
(d) small, producing nectar and dry pollen
Answer:
(b) small, producing large number of dry pollen grains

Question 3.
Which of the following statements about sporopollenin is false?
(a) Exine is made up of sporopollenin
(b) Sporopollenin is one of the resistant organic materials
(c) Exine has apertures called germ pores where sporopollenin is present
(d) sporopollenin can withstand high temperatures and strong acids
(e) No enzyme that degradessporopollenin is so far known
Answer:
(c) Exine has apertures called germ pores where sporopollenin is present

Question 4.
Egg apparatus of angiosperms consist of
(a) one synergid and two egg cells
(b) two synergid and one egg cells
(c) one central cell, two synergid, and three antipodal cells
(d) one egg cell, two polar nuclei, and three antipodal cells
Answer:
(b) two synergid and one egg cells

Question 5.
In some organisms, karyokinesis is not followed by cytokinesis as a result of which, multinucleate condition arises leading to the formation of syncytium. The perfect example for this is
(a) appearance of a furrow in cell membrane
(b) liquid endosperm in coconut
(c) sexual reproduction
(d) fertilization
Answer:
(b) liquid endosperm in coconut

Question 6.
During the formation of embryo sac, the functional megaspore undergoes
(a) two mitotic divisions
(b) two meiotic division
(c) three meiotic division
(d) three mitotic divisions
Answer:
(d) three mitotic divisions

Question 7.
One advantage of cleistogamy is
(a) it leads to greater genetic diversity
(b) seed dispersal is more efficient and widespread
(c) seed set is not dependent on pollinators
(d) each visit of a pollinator results in transfer of hundreds of pollen grains
Answer:
(c) seed set is not dependent on pollinators

Question 8.
Which one of the following statements is not true?
(a) Pollen grains are released from anthers at 2- celled state
(b) Sporogenous cell directly behaves as he megaspore mother cell
(c) Megaspore divides twice to form an eight nucleate embryo sac
(d) Egg and synergids always lie near the micropylar end of ovule
Answer:
(c) Megaspore divides twice to form an eight nucleate embryo sac

Question 9.
Sporopollenin is chemically
(a) homopolysaccharide
(b) fatty substance
(c) protein
(d) heteropolysaccharide
Answer:
(d) heteropolysaccharide

Question 10.
Which one of the following pairs of plant structures has haploid number of chromosomes?
(a) Megaspore mother cell and antipodal cells
(b) Egg cell and antipodal cells
(c) Nucellus and antipodal cells
(d) Egg nucleus and secondary nucleus
Answer:
(b) Egg cell and antipodal cells

Question 11.
What does the filiform apparatus do at the entrance into ovule?
(a) It helps in the entry of pollen tube into a synergid
(b) It prevents entry of more than one pollen tube into the embryo sac
(c) It brings about opening of the pollen tube
(d) It guides pollen tube from a synergid to egg
Answer:
(a) It helps in the entry of pollen tube into a synergid

Question 12.
Which of the following plant products is the hardest?
(a) Lignin
(b) Cutin
(c) Suberin
(d) Sporopollenin
Answer:
(d) Sporopollenin

Question 13.
A typical angiosperm embryo sac at maturity, is
(a) 4 – nucleate – 2 celled
(b) 8 – nucleate – 7 celled
(c) 4- nucleate – 4 celled
(d) 8 – nucleate – 2 celled
Answer:
(b) 8 – nucleate – 7 celled

Question 14.
Why sometimes, even diploid offspring is produced through parthenogenesis?
(a) When offspring is produced without fertilization of diploid egg cell
(b) When offspring is produced through fertilization of diploid egg cell
(c) When offspring is produced without fertilization of haploid egg cell
(d) When offspring is produced through fertilization of haploid egg cell
Answer:
(a) When offspring is produced without fertilization of diploid egg cell

Question 15.
Pollen grains are stored for long period without losing its viability in
(a) liquid nitrogen
(b) liquidsulphur
(c) liquidsulphur at-1960c
(d) liquidsulphur at-196.50c
Answer:
(a) liquid nitrogen

Question 16.
Filiform apparatus of an embryosac is located at
(a) wall of embryosac
(b) chalazal region
(c) micropylar region
(d) middle of polar nuclei
(e) none of the above
Answer:
(c) micropylar region

Question 17.
Double fertilization is very common in
(a) angiosperm
(b) gymnosperm
(c) pteridophytes
(d) bryophytes
Answer:
(a) angiosperm

Question 18.
In Citms and mango the polyembryony is the special feature of occurance of
(a) more than one embryo
(b) more than one zygote
(c) more than one embyosac
(d) all the above
Answer:
(d) all the above

Question 19.
Triple fusion takes place in angiosperm is due to
(a) fusion of three polar nuclei
(b) fusion of synergid and polar nuclei
(c) fusion of three haploid nuclei
(d) fusion of gametes
Answer:
(c) fusion of three haploid nuclei

Question 20.
In 40 percent of angiosperms, pollen grains are shed at
(a) 2-celled
(b) 3-celled
(c) 4-celled
(d) 5- celled
Answer:
(b) 3-celled

Question 21.
In artificial hybridization bagging is done to
(a) avoid wanted pollen
(b) avoid unwanted pollen
(c) prevent the entry of unwanted pollinators
(d) allow the self pollination
Answer:
(b) avoid unwanted pollen

Question 22.
How many mitotic divisions are required for the formation of mature embryosac
(a) 4
(b) 3
(c) 5
(d) 2
Answer:
(b) 3

Question 23.
The allergies and bronchial afflictions in some people often leading to chronic respiratory disorders. It is due to
(a) pollen of parthenium
(b) pollen of hibiscus
(c) pollen of Acasia
(d) both a and c
Answer:
(d) both a and c

Students can Download Chapter 12 Consumer Protection Questions and Answers, Plus Two Business Studies Chapter Wise Questions and Answers helps you to revise the complete Kerala State Syllabus and score more marks in your examinations.

Kerala Plus Two Business Studies Chapter Wise Questions and Answers Chapter 12 Consumer Protection

Plus Two Business Studies Consumer Protection One Mark Questions and Answers

Question 1.
Consumer Protection Act was passed in the year ……………..
(a) 1964
(b) 1956
(c) 1932
(d) 1986
Answer:
(d) 1986

Question 2.
When did the provisions of consumer Protection Act come into force?
Answer:
1 July 1987

Question 3.
Which is acclaimed to be the ‘Magna Carta’ of Indian consumers?
Answer:
Consumer Protection Act 1986

Question 4.
Consumer’s right to information means
(a) Right to advocate consumer’s interest.
(b) Right to be informed about the quality, quantity, price, etc. of the product.
(c) Right to be protected against marketing of hazardous goods.
Answer:
(b) Right to be informed about the quality, quantity, price, etc. of the product.

Question 5.
World consumer rights day is observed on ……………
Answer:
March 15

Question 6.
“Cigaratte smoking is injurious to health”. This information is mandatory in all cigarette packets. From this example identify consumer rights.
Answer:
Right to be Informed

Question 7.
Which consumer right gives the business firm freedom to set up their own consumer service & grievances cell?
Answer:
Right to be heard

Question 8.
Which consumer right entitles the consumer to get relief in case the product or service falls short of his expectation?
Answer:
Right to seek redressal

Question 9.
Which consumer right have access to a variety of products and services?
Answer:
Right to choose

Question 10.
Which consumer right suggests that a consumer must be protected from goods and services hazardous to life and health?
Answer:
Right to safety

Question 11.
Which judicial machineries are available to deal with consumer grievances?
Answer:

1. District Forum
2. State Commission
3. National Commission

Question 12.
Mr. X purchased a car for Rs.15 lakh but he is not satisfied with the quality and performance of the car. The company of the car did not provide any remedy to him. Under which authority of consumer protection Act 1986 can file an appeal?
Answer:
District Forum

Question 13.
Maximum amount of compensation that can be claimed in District consumer forum should not exceed:
Answer:
20 Lakhs

Question 14.
If a consumer is not satisfied with the order of the District forums, where can he appeal?
Answer:
State Commission

Question 15.
Find the odd one and state reason District Forum, State Commission, Law Adalats, National commission
Answer:
Law Adalats. All others are redressel agencies.

Question 16.
Within what period of purchase can the complaint be filed under Consumer Protection Act?
Answer:
Within 3 months

Question 17.
Name the apex institution to seek redressal under Consumer Protection Act, 1986.
Answer:
National Commission

Question 18.
When the value of compensation claimed is in between 20 lakhs and 1 crore complaints can be filled with:
(a) District Forum
(b) State Commission
(c) National Commission
Answer:
(b) State Commission

Question 19.
ISI mark is given by
(a) Ministry of Finance.
(b) Ministry of Environment and Forest.
(c) Bureau of Indian Standard
(d) State Government.
Answer:
(c) Bureau of Indian Standard

Question 20.
…………………… is a means of consumer protection
to provide legal representation to previously represented groups and interest.
Answer:
Public Interest Litigation (PIL)

Question 21.
Amit wants to buy Gold Jewellery. As a knowledgeable customer how can he be sure about the quality of the jewellery?
Answer:
Hallmark

Question 22.
Which quality certification mark is used in case of electrical goods?
Answer:
ISI

Question 23.
Name the quality certification mark used is case of food products.
Answer:
F.P.O.

Question 24.
On which type of products can Eco Mark is used?
Answer:
Eco-friendly products

Question 25.
Smt. Sindhu purchased a silk saree costing Rs. 5,000. After first wash, it has lost the colour and caused huge loss to her. She lodged a complaint to the redressal forum. It was held that she will be given a sum of Rs. 5,000 as compensation. Identify the redressal forum she might have lodged the complaint.
Answer:
District Forum

Question 26.

A	B
a) The Consumer Protection Act	a) 1976
b) The Prevention of Food Adulteration Act	b) 1986
c) The Bureau of 1 Indian Standards Act	c) 1986
d) The Standards of Weights and Measures Act	d) 1954

Answer:

A	B
a) The Consumer Protection Act	a) 1986
b) The Prevention of Food Adulteration Act	b)1954
c) The Bureau of Indian Standards Act	c) 1986
d) The Standards of Weights and Measures Act	d) 1976

Question 27.
Demand the bill on purchase is the ………………. of a consumer.
Answer:
Responsibility

Question 28.
Where can a customer appeal within 30 days, if he is not satisfied with the order of National Commission?
Answer:
In Supreme Court

Plus Two Business Studies Consumer Protection Two Mark Questions and Answers

Question 1.
Mr. Bejoy purchases a new computer from Ajitha traders. They give two years replacement guarantee. After six months use, the computer system fails to perform. Mr. Bejoy approaches the traders for replacement. But the traders refuse replacement.

1. Identify the law violated by the traders.
2. Point out redressal agencies where Bejoy should complain against the traders.

Answer:
1. Consumer Protection Act 1986.
2. Mr. Bejoy can approach the following redressal agencies for compensation.

• District Forum
• State Commission
• National Commission.

Question 2.
Mrs. Fathima, a house wife, while cooking food, the pressure cooker exploded, causing a big injury. She lodged a complaint to the redressal forum. Accordingly, the forum’s verdict was to pay a sum of Rs. 10,000/- as compensation.

1. Identify the right which has been violated.
2. In which redressal forums she might have lodged the complaints.

Answer:

1. Right to safety
2. District Forum

Question 3.
Cite a few examples of practices usually adopted by businessmen with view to deceiving the consumers and thereby exploit the poor customers to the maximum.
Answer:
Adulteration, black marketing, false weights, Poor quality of goods, duplication of brands, increasing the price of the product, etc.

Question 4.
If a case is decidedly the District Forum, can it be appealed before the Supreme Court.
Answer:
No. It can be challenged in the State Commission.

Question 5.
Name any two consumer organizations engaged in protecting and promoting consumers interest.
Answer:
Some of the important consumer organisations and NGOs engaged in consumer protection are

• Consumer Co-ordination Council, Delhi.
• Voluntary Organisation in Interest of Consumer Education (VOICE).
• Common Cause, Delhi.
• Consumer Protection Council, Ahmedabad.
• Consumer Guiderice Society of India, Mumbai.
• Consumer’s Association, Kolkatta, etc.

Question 6.
Who is a Consumer?
Answer:
Consumer: Under the Consumer Protection Act, a consumer is defined as

1. Any person who buys any goods for a consideration.
2. Any person who hires or avails of any service, for a consideration.

Plus Two Business Studies Consumer Protection Three Mark Questions and Answers

Question 1.
Anju while on her shopping time is always vigilant to see that the products purchased come under “Eco mark”.

1. Why does she look for ‘eco mark’ while shopping? State its merits?
2. Cite a few examples of products which come under eco mark system.

Answer:
The ‘Eco mark’ label ensures consumers environment friendly products. Such products are not harmful to the environment in their manufacture, use and disposal.
E.g. AGMARK for wheat, flour, spices, etc.

Question 2.
Explain, in brief, any 3 reasons as to why consumer protection is needed in India.
Answer:

1. To protect the consumers against products that are unsafe to health and hygiene.
2. To protect the consumer against deceptive and unfair trade practices and to provide him with ad-equate means to get his grievance redressed.
3. To prevent abuse of monopoly position.

Question 3.
Mr. Balu gave a new dictionary as a gift to Manu, one of his friends. Manu found that some of its pages are unreadable due to over spreading of ink. He approached the shop keeper and demanded to replace it. But the shop keeper refused to replace the dictionary on the argument that Manu is not a consumer for him. Suggest your opinion.
Answer:
No. The argument of the shopkeeper is wrong. Manu is also a consumer. The term consumer means:

1. A person who buys any goods for a consideration.
2. A person who hires or avails of any services for a consideration.
3. Anyone who uses goods bought or services hired exclusively for earning livelihood by self employment.

Plus Two Business Studies Consumer Protection Four Mark Questions and Answers

Question 1.

1. Which is acclaimed to be the ‘Magna Carta’ of Indian Consumers?
2. Explain its importance.

Answer:

1. Consumer Protection Act, 1986.
2. Importance of Consumer Protection Act

a. From Consumers’ point of view:

• It is necessary to educate the customers about their rights.
• Consumers need to be organised in the form of consumer organisations which would take care of their interests.
• To protect the consumers from unscrupulous, exploitative and unfair trade practices.

b. From the Point of View of Business:

• Business firms should aim at long-term profit maximization through customer satisfaction.
• Business organisations use resources which belong to the society.
• A business has social responsibilities towards various interest groups.
• It is the moral duty of any business to take care of consumer’s interests and avoid any form of their exploitation.
• A business engaging in any form of exploitative trade practices would invite government intervention or action.

Question 2.
Who can file a complaint under Consumer Protection Act,1986?
Answer:
Complaint before the appropriate consumer forum can be made by

1. Any consumer.
2. The Central Government or any State Government.
3. One or more consumers, on behalf of numerous consumers having the same interest.
4. A legal heir or representative of a deceased consumer.

Question 3.
Explain any four functions of consumer association.
Answer:
Role of Consumer Organisations and Non-governmental Organizations (NGOs.)

1. Educating the general public about consumer rights by organising training programmes, seminars and workshops.
2. Publishing periodicals and other publications.
3. Collecting various samples of different goods and testing their quality.
4. Encouraging consumers to protest against exploitative and unfair trade practices of sellers.
5. Providing legal assistance to consumers by way of providing aid, legal advice, etc.
6. Filing complaints in appropriate consumer courts on behalf of the consumers.
7. Encouraging consumers to boycott defective goods.
8. Encouraging the consumers to purchase consumer friendly products.
9. Taking an initiative in filing cases in consumer courts in the interest of the general public.

Plus Two Business Studies Consumer Protection Five Mark Questions and Answers

Question 1.
What are the various remedies available to a consumer under Consumer Protection Act, 1986?
Answer:
Relief Available to Consumers (Remedies)

1. To remove the defect in goods or deficiency in service.
2. To replace the defective product with a new one, free from any defect.
3. To refund the price paid for the product.
4. To pay a reasonable amount of compensation for any loss or injury suffered by the consumer.
5. To discontinue the unfair/restrictive trade practice.
6. Not to offer hazardous goods for sale.
7. To withdraw the hazardous goods from sale.
8. To issue corrective advertisement to neutralise the effect of a misleading advertisement.

Question 2.
Consumers are often exploited by profiteering business. What are the measures available to safeguard them?
Answer:
Ways and Means of Consumer Protection
1. Self Regulation by Business:
Many firms have set up their customer service and grievance cells to redress the problems and grievances of their consumers.

2. Business Associations:
The Associations of trade, commerce and business-like Federation of Indian Chambers of Commerce of India (FICCl) and Confederation of Indian Industries (CII) have laid down their code of conduct for their members in their dealings with the customers.

3. Consumer Awareness:
A consumer, who is well informed about his rights, responsibilities and the reliefs available to him, would be in a position to raise his voice against any unfair trade practices or unscrupulous exploitation.

4. Consumer Organisations:
Consumer organisations play an important role in educating consumers about their rights and providing protection to them.

5. Government:
The government can protect the interests of the consumers by enacting various legislations.

Question 3.
What are the responsibilities of a consumer?
Answer:
Consumers Responsibilities

1. Be aware about various goods and services available in the market.
2. Buy only standardised goods as they provide quality assurance.
3. Learn about the risks associated with products and services, follow manufacturer’s instructions and use the products safely.
4. Read labels carefully so as to have information about prices, net weight, manufacturing and expiry dates, etc.
5. Choose only from legal goods and services.
6. Ask for a cash memo on purchase of goods or services.
7. File a complaint in an appropriate consumer forum in case of poor quality of goods or services.
8. Form consumer societies which would play an active part in educating consumers.

Plus Two Business Studies Consumer Protection Eight Mark Questions and Answers

Question 1.
In a classroom discussion Vinod argues that Consumers have no right while purchasing or using a product.

1. Do you agree?
2. Explain various rights of consumers.

Answer:
Consumer Rights:
1. Right to Safety: The consumer has a right to be protected against goods and services which are hazardous to life and health.

2. Right to be Informed: The consumer has a right to have complete information about the product he intends to buy including its ingredients, date of manufacture, price, quantity, directions for use, etc.

3. Right to Choose: The consumer has the freedom to choose from a variety of products at competitive prices.

4. Right to be Heard: The consumer has a right to file a complaint and to be heard in case of dissatisfaction with goods or services.

5. Right to seek Redressal: The consumer has a right to get relief in case the product or service falls short of his expectations.

6. Right to Consumer Education: The consumer must be educated about the rights and remedies available under different laws.

Question 2.
Prepare an assignment on various consumer responsibilities.
Answer:
Consumers’ Responsibilities:

1. Be aware about various goods and services available in the market.
2. Buy only standardised goods as they provide quality assurance.
3. Learn about the risks associated with products and services, follow manufacturer’s instructions and use the products safely.
4. Read labels carefully so as to have information about prices, net weight, manufacturing and expiry dates, etc.
5. Choose only from legal goods and services.
6. Ask for a cash memo on purchase of goods or services.
7. File a complaint in an appropriate consumer forum in case of poor quality of goods or services.
8. Form consumer societies which would play an active part in educating consumers.

Students can Download Chapter 8 Biodiversity and Conservation Questions and Answers, Plus Two Zoology Chapter Wise Questions and Answers helps you to revise the complete Kerala State Syllabus and score more marks in your examinations.

Kerala Plus Two Zoology Chapter Wise Questions and Answers Chapter 8 Biodiversity and Conservation

Plus Two Zoology Biodiversity and Conservation One Mark Questions and Answers

Question 1.
The species diversity of plants on earth will be
(a) 2.4%
(b) 22%
(c) 8.1%
(d) 85%
Answer:
(b) 22%

Question 2.
Which of the following rain forest is home to more than 40,000 species of plants, 3,000 of fishes, 1,300 of birds, 427 of mammals, 427 of amphibians, 378 of reptiles and more than 1,25,000 invertebrates?
(a) Amazonian
(b) Tropical
(c) Arctic tundra
(d) Temperate
Answer:
(a) Amazonian

Question 3.
Which one of the following pairs of geographical areas shows maximum biodiversity in our country?
(a) Sunderbans and Rann of Kutch
(b) Eastern ghats and West Bengal
(c) Eastern Himalaya and Western Ghats
(d) Kerala and Punjab’
Answer:
(c) Eastern Himalaya and Western Ghats

Question 4.
Which of the following is most dangerous to wildlife?
(a) Overexploitation
(b) Man-made forest
(c) Habitat destruction
(d) Introduction of foreign species
Answer:
(c) Habitat destruction

Question 5.
The extinction of cichlid fish in the lake is due to
(a) habitat loss and fragmentation
(b) overexploitation
(c) Alien species invansion
(d) Co-extinctions
Answer:
(c) Alien species invansion

Question 6.
Aquatic environment of Kerala is facing serious threat by alien species invasion. Can you say anyone example of a species by which our indigenous plants and animals are facing greater threat.
Answer:
Eichornia

Question 7.
Write the significance of seed banks in biodiversity conservation?
Answer:
Seeds of different genetic strains of commercially important plants and other plants can be kept for a long period.

Plus Two Zoology Biodiversity and Conservation Two Mark Questions and Answers

Question 1.
Global diversity of invertebrates are shown below:-

1. Which invertebrate group shows highest biodiversity and why?
2. Among vertebrates, which group has the highest biodiversity?

Answer:

1. Insects (Arthropods), their cuticular exoskeleton gives high survival and diversity.
2. Fishes

Question 2.
Define co-extinction.
Answer:
When a species becomes extinct, the plant and animal species associated with it also become extinct. This is called co-extinction.

Question 3.
Now a days the area of sacred grooves decreased. Suggest the role of sacred grooves in conservation of biosphere?
Answer:
Sacred grooves are tracts of forests set aside by many cultures, where all the trees and wild life are given total protection.

Question 4.
Introduction of exotic species is one of the major threats to biodiversity. Analyse this statement with any four examples in your locality.
Answer:
When exotic species are introduced, some may turn invasive and cause extinction of ndigenous species.
Eg: Carrot grass, Eichornia, Lantana, African cat fish.

Question 5.
“The biological wealth of our planet has been declining rapidly and the accusing finger is clearly pointing to human activities.”

1. Mention any two activities leading to the loss of biodiversity.
2. Mention the different ways to conserve biodiversity.

Answer:

1. Habitat destruction Pollution and overexploitation
2. i) Insitu conservation – National parks, Biosphere reserve etc.
   ii) Exsitu conservation – Zoo, Botanical garden, Cryopreservation, etc

Question 6.
Arrange the following terms into two-column with proper title (Biological reserves, Zoological park, Sacred groves, National park, Cryopreservation of gametes, Wild life sanctuaries, In vitro fertilization, Botanical garden).
Answer:

Exsitu conservation	Insitu conservation
Zoological park	Biological reserves
Cryopreservation of gametes	Sacred groves
Invitro fertilization	National park
Botanical garden	Wild life sanctuaries

Question 7.
“Conservation of nature” is a slogan which is heard all over the world. Proposed by environmentalists in this conservation of biodiversity is very important.

1. What are the different levels of biodiversity?
2. Which are the threats of biodiversity?

Answer:
1. different levels of biodiversity

• genetic diversity
• Species diversity
• Ecological diversity

2. threats of biodiversity

• Habitat loss and fragmentation
• Over-exploitation
• Alien species invasions
• Co-extinction

Question 8.
Alien species invasion is one of the causes of biodiversity loss.

1. Do you agree with this statement?
2. Site any two examples of alien species in your locality.

Answer:

1. Yes. Alien species cause decline or extinction of indigenous species. Eg: Lantana
2. Eichhornia

Question 9.
The need for conservation of biodiversity is undoubtedly inevitable for the future existence of man kind.

1. Name the strategies involved in biodiversity conservation. Give examples for each.
2. What is endemism?
3. Expand IUCN.

Answer:

1. i) Insitu conservation
Eg: Biosphere, reserve, national parks, and wild life sanctuaries.

ii) Ex-situ conservation
Eg: Zoo, Botanical garden, tissue culture, seed banks.

2. Species confined to a region and not found anywhere else. Endemic species are rich in hotspots.

3. International Union for conservation of nature and natural resources.

Question 10.
Scientists estimate that species diversity decreases as we move away from equator towards the poles. Tropical Amazonian rainforest in South America has the greatest diversity on earth.

Do you agree that there is something so special about tropics that might account for greater biodiversity. Justify your answer.
Answer:
Yes. The specialities of tropics are
They remained undisturbed for millions of years. The tropical environment is less seasonal, more constant and predictable. There is more solar energy, which contribute to higher productivity.

Question 11.
The accelerated rates of species extinctions that the world is facing now are largely due to human activities.

1. Mention the evil quatret which cause extinction.
2. Name two ex-situ method to conserve diversity.

Answer:
1. The evil quatret which cause extinction

• Habitat loss
• Overexploitation
• Alein species invasion
• Coextinction

2. Two ex-situ method to conserve diversity

• Zoo
• Botanical garden

Question 12.
“The Central Govt. declared the buffer zone to the silent valley National Park.” Predict advantages of this decision.
Protective area
Answer:

• Research/Education
• Reduce human settlement
• Reduce destruction of forest resource
• Area of park increase
• Reduce the pressure

Question 13.
Alien species are a threat to native species, justify taking examples of an animal and a plant alien species.
Answer:
The Nile Perch introduced in lake Victora in East Africa led eventually to the extinction of more than 200 species of Ci child fish in the lake. African cat fish (Clariasgariepinus) for aquaculture purpose is posing threat to the indigenous catfishes in our rivers.

Invasive weed species Eicchornia (water hyacinth). Parthenium (carrot grass). Lantana have posed a threat to our native species.

Question 14.
“We can develop a proper perspective through an analogy. The rivet popper hypothesis’ regarding the importance of species diversity to the ecosystem”. Substantiate?
Answer:
Analogy rivet popper hypothesis, used by Paul Ehrlich, indicates the importance of each species to the ecosystem. In a plane (ecosystem) all parts are joined together using thousands of rivets (species).

The extinction of a species affects the normal functioning of ecosystem, like removal of rivets of a plane. Damage of more number of species affects the ecosystem dangerously.

Question 15.
In our biosphere, immense diversity exists in all levels of biological organisation. Describe the most important levels of biodiversity.
Answer:

1. Genetic diversity: Diversity of genes within a species.
2. Species diversity: The diversity at the species level.
3. Ecological diversity: Diversity at the ecosystem level.

Question 16.
The extinction of the bird ‘Dodo’ in Mauritius island also lead to the extinctinon of the tree named ‘Calvaria major’. Explain the process that is a cause of a biodiversity loss?
Answer:
Co-extinction. When a species becomes extinct, the plant and animal species associated with it in an obligatory way also become extinct. This is called co-extinction.

Analogy rivet popper hypothesis, used by Paul Ehrlich, indicates the importance of each species to the ecosystem. In a plane (ecosystem) all parts are joined together using thousands of rivets (species).

The extinction of a species affects the normal functioning of ecosystem, like removal of rivets of a plane. Damage of more number of species affects the ecosystem dangerously.

Question 17.
‘Evil Quartet’ is a sobriquet used to describe the cause of biodiversity loss.

1. What are the evil quartets of biodiversity loss?
2. Write two ill effects of biodiversity loss?

Answer:

1. Habitat loss and fragmentation, Over-exploitation, Alien species invasion and Co-extinction.

2. effects of biodiversity loss

• decline in plant production
• Lowered resistance to environment

Question 18.
‘Amazon forests are called the lungs of the planet’ Why?
Answer:
Amazon rain forest is huge and harbor millions of species and it is estimated to produce, through photosynthesis, 20% of the total oxygen in the earth’s atmosphere.

Question 19.
The following pie diagram represents global biodiversity of invertebrates and vertebrates. Complete the graph by giving suitable group of animals to the missing sectors A and B.

Answer:

1. Insects
2. Fishes

Question 20.
‘India is one of the 12 Mega Biodiversity countries of the world’. Justify?
Answer:
India has approximately 8.1% of global species diversity, probably has more than 100000 species of plants and 200000 animal species, India has western Ghats, Indo Burma, and Himalaya as hotspots.

Question 21.
‘Gametes of threatened species can be preserved in a viable and fertile condition for a long time’

1. Identify the preservation technique used?
2. Why is it considered as an Ex-situ conservation approach?

Answer:

1. Cryopreservation
2. In ex-situ approach threatened animals/ plants/ gametes/ seeds are taken from their natural habitat and placed in special condition.

Question 22.
Categorize the following into ex-situ and in-situ conservation strategies. Seed banks, Tissue culture, sacred grooves, national parks, zoological parks, biosphere reserve, botanical garden, sanctuaries.
Answer:

• Ex-situ: Sacred groves, National Park, Biosphere reserve, Sanctuaries
• In-situ: Tissue culture, Zoological park, seed banks, Botanical garden.

Question 23.
Compare in situ and ex situ conservation strategies with examples?
Answer:
1. In-situ: Protect the whole ecosystem, its biodiversity at all levels. Eg: Biosphere reserve, national park, sanctuaries, etc.

2. Ex-situ: it is the strategy to protect threatened and endangered species which needs urgent measures to save it from extinction. Eg: zoo, botanical garden, seed bank, etc.

Question 24.

Read the statement and state whether true or false.

1.

• Endangered species are more in reptiles than in birds and mammals.
• Critically endangered species are more in birds than in reptiles and mammals.

2. What is the role of Alien species invasions in extinction?

Answer:

1.

• True
• False

2. Alien species are foreign species, when introduced, some of them turn invasive and cause decline or extinction of indigenous species.

Question 25.
What are hot spots in biodiversity? Why endemism is considered an important criteria for identifying hot spots?
Answer:
1. Hot spots: are the regions with high levels of species richness and high degree of endemism.

2. Endemism: is the number of species confined to a particular region and not found anywhere else. High degree of endemism means species richness is more and are not found anywhere else and should be protected to prevent extinction.

Question 26.
The species diversity of the plants (22%) is much less that of animals (72%). What could be the explanations to how animals achieved greater diversification?
Answer:
Compared to plants, animals have increased size and genetic variation. Also, the animals possess complex nervous system to control and coordinate various body activities.

Animals possess receptor organs for receiving various environmental stimuli and able to respond against them. The ability of locomotion is also a factor for greater diversification of animals.

Plus Two Zoology Biodiversity and Conservation Three Mark Questions and Answers

Question 1.
Amazonian rain forest has the greatest biodiversity on earth. List any two hypothesis that are proposed by the biologists to account for the greater biological diversity.
Answer:
The hypothesis are:
1. Speciation is generally a function of time; unlike temperate regions which are subjected to frequent glaciations in the past, tropical latitudes have remained undisturbed for millions of years and hence had a long time for species diversification.

2. Tropical environments are less seasonal, relatively more constant and predictable; such constant environments promote niche specialization and lead to a greater species diversity.

3. There is more solar energy available in the tropics, which contributes to higher productivity; this in turn might contribute indirectly to species diversity.

Question 2.
Introduction of exotic species is one of the major threats of biodiversity.

1. Cite any two examples of these exotic species in your locality.
2. Recent illegal introduction of a fish for aquaculture poses a threat to indigenous catfishes in our rivers. Name it.
3. How co-extinctions affects biodiversity?

Answer:

1. Eichornia- Lantana Camera
2. African catfish (clarius gariepinus)
3. When a species becomes extinct, the species associated with it in an obligatory way also become extinct. This is called co-extinction.

Question 3.
Observe the graph.

1. What does this graph represent?
2. Who proposed this relationship?
3. What does the alphabets S, C, A, Z represent?

Answer:

1. Species – Area relationships
2. Alexander Von Humboldt
3. S-Species richness A – Area Z – Slope of the line C-Y-Intercept.

Question 4.
There are many reasons, some obvious and others not so obvious, but all equally important to conserve biodiversity. They are grouped into three categories.

1. Name them.
2. Among 3 categories, which one has a scope of ‘bioprospecting’, for exploring biodiversity for products of economic importance.
3. Give examples for Ex-situ conservation.

Answer:

1. Narrowly utilitarian argument.
   Broadly utilitarian argument.
2. Narrowly utilitarian argument.
3. Zoological parks, botanical gardens, Cryopreservation, tissue culture, seed banks, pollen banks, etc.

Question 5.
Bio-diversity is not uniform throughout the world, but shows a rather uneven distribution.

1. What is latitudinal gradients in diversity?
2. What is so special about tropics that might account for their greater biological diversity.
3. Which is the area that has the highest biodiversity on earth?

Answer:

1. The distribution of diversity of plants and animals decreases as we move away from equator towards the poles.

2. biological diversity

• Tropical latitudes have remained relatively undisturbed for millions of years, thus had a long evolutionary time for species diversification.
• Tropical environments are less seasonal, relatively more constant and predictable.
• More solar energy is available which contributes to high productivity and greater diversity.

3. Amazonian rain forest in South America.

Question 6.
Observe the given graph

1. What does the above graph represent?
2. What does S and A indicate?
3. Write the significance of ‘Z’ value?

Answer:

1. Species area relationship
2. S = Species richness, A = area
3. Z is the slop of the line (regression coefficient).

Question 7.
How do the following factors affect biodiversity? Answer with suitable examples.

1. Alien species invasion
2. Co extinction
3. Overexploitation

Answer:
1. Alien species turn invasive and cause decline or extinction of indigenous species. Nile perch introduced into Lake Victoria in east Africa led to the extinction of more than 200 species of cichlid fish in the lake.

2. When a species become extinct the plants and animals associated with it in an obligatory way also become extinct, coevolved. Plant-pollinator mutualism where extinction of one species leads to the extinction of the other.

3. It happen when need turns greed and over utilization of natural resources in an irrecoverable way. Extinction of Steller’s sea cow, passenger pigeon was due to humans.

Question 8.
Narrow utilitarian, broad utilitarian and ethical arguments are the three major arguments/ reasons for conserving biodiversity. Briefly explain the basis of these three arguments?
Answer:
1. Narrowly utilitarian:
Humans get economic benefits from nature food (cereals, pulses, fruits), firewood, fibre, construction material, industrial products (tannins, lubricants, dyes, resins, perfumes) and products of medicinal importance.

2. broadly utilitarian:
Biodiversity plays a major role in ecosystem services. Amazon forest is through photosynthesis produce 20 percent of the total oxygen in the earth’s atmosphere.

Pollination is another ecosystems service by bees, bumblebees, birds, and bats. Nature provides aesthetic pleasures of watching spring flowers in full bloom and bulbul’s song in the morning.

3. Ethical:
Every species has an intrinsic value so they are conserved for future generations.

Question 9.
What are the factors responsible for the greater biodiversity in tropical regions?
Answer:

1. Tropics have remained undisturbed for millions of years and had a long evolutionary time for species diversification.
2. Constant and predictable tropical environments promote niche speciation and greater diversity.
3. More solar energy in tropics contributes higher productivity and indirectly to greater diversity.

Question 10.
Write the three components of Biodiversity. Select the component which deals with ecosystem levels of biodiversity?
Answer:

• Genetic diversity
• Species diversity
• Ecological diversity.

Plus Two Zoology Biodiversity and Conservation NCERT Questions and Answers

Question 1.
Name the three important of biodiversity.
Answer:

• Genetic diversity
• Species diversity
• Ecosystem diversity

Question 2.
How do ecologists estimate the total number of species present in the world?
Answer:
They make a statistical comparison of the species richness of exhaustively studied groups of insects of the temperate and tropical regions and extrapolate this ratio to other groups of animals and plants to calculate gross estimate of the total number of species present on the earth.

Question 3.
Give three hypothesis for explaining why tropics show greatest levels of species richness.
Answer:
Biodiversity is not uniformly distributed throughout the world. Polar regions have very little biodiversity whereas South America has the greatest biodiversity on the earth. There are many hypothesis for higher biodiversity in tropics:

1. There are no unfavourable seasons in tropics. Continued favourable environmental condition has helped tropical organisms to flourish more.

2. There is more solar energy available in the tropics due to which productivity is higher and this contribute to greater diversity.

The tropical environment is older thus allowing more time for the evolution of greater number of plants and animals.

Question 4.
What is the significance of the slope of regression in a species-area relationship?
Answer:
Alexander Von Humboldt observed that within a definite region the species richness increases upto some extent with increase in area. This relationship between species richness and area is a hyperbola fora large variety of taxa.
On a logarithmic scale it is a straight line
Log S = log C + Z log A
Where S = species richness
Z = slope of line (regression coefficient)
C = Y-intercept
A = Area
Z is generally 0.1 -0.2 regardless of taxonomic group or region i.e., when analysis of speices-area relationship is done among small areas, the values of slopes of regression are remarkably similar regardless of the taxonomic group or the region.

If analysis of species-area relationship is done among very large like a whole continent, the slope of regreesion line would be much steeper.

Question 5.
What are the major causes of species losses in a geographical region?
Answer:

• Habit loss and fragmentation
• Over-exploitation
• Introduction of exotic species
• Co-extinctions.

Question 6.
Can you think of a situation where we deliberately want to make a species extinct? How would you justify it?
Answer:
This situation may appear when alien species is introduce unintentionally or deliberately into an area. Some of them may become invasive and cause damage to indigenous species.

For example Nile perch introduced into lake Victoria in East Africa led to extinction of 200 species of Cichlid fish in the lake. Introduction of African catfish Clariasgariepinuslor aquaculture is threatening the indigenous catfishes in rivers of India.

Question 7.
What are sacred groves? What is their role in con¬servation?
Answer:
Sacred groves are sacred forest patches around places of forest. In such cases, nature is protected by prevailing religious and cultural traditions. Here tracts of forests are set aside and all plants and animals are venerated and provided with complete protection.

Some examples of sacred groves are Khasi and initial hills in Meghalaya. Aravalli hills in Rajasthan, Western ghat regions of Karnataka, Maharashtra and Sargiya, Chanda and Bastar areas of M.P. In Sikkim, Khecheopalri lake is declared sacred lake by people, thus protecting the aquatic flora and fauna.

Many rare and threatened plants have been protected in sacred groves of Meghalaya. Such areas have been found to be most undisturbed and they are usually surrounded by most degraded landscapes.

Question 8.
Among the ecosystem services are control of floods and soil erosion. How is this achieved by the biotic components of the ecosystem?
Answer:
Earth’s rich biodiversity is vital for indirect benefits like control of floods and soil erosion. Species richness checks soil erosion by binding the soil particles thereby reducing the rate of water velocity, hence reducing the chances of floods.

Question 9.
The species diversity of plants (22 percent) is much less than that of animals (72 percent). What would be the explanations to how animals achieved greater diversification?
Answer:
Animals bear nervous system for control and co-ordination of activities. They also bear receptors to respond to environment stimuli. Many responses become adaptive for survival. Thus animal bears higher species diversity than plants.

Plus Two Zoology Biodiversity and Conservation Multiple Choice Questions and Answers

Question 1.
Spot out the zone of our country considered as the hot spot of biodiversity and regarded as the ‘Cradle of Speciation’.
(a) Western ghats
(b) North East
(c) Himalayan base
(d) Deccan plateau
Answer:
(b) North East

Question 2.
One of the most important functions of botanical gardens is that
(a) one can observe tropical plants there
(b) they allow exsitu conservation of germplasm
(c) they provide the natural habitat for wild life
(d) they Provide a beautiful area for recreation
Answer:
(b) they allow exsitu conservation of germplasm

Question 3.
The diversity of the habitats over the total geographical area is called
(a) alpha diversity
(b) beta diversity
(c) gamma diversity
(d) delta diversity
Answer:
(c) gamma diversity

Question 4.
Biosphere reserves differ from national parks and wild life sanctuaries because in the former
(a) human being are not allowed to enter
(b) people are an integral part of the system
(c) plants are paid greater attention than the animals
(d) living Organisms are brought from all over the world and preserved for posterity
Answer:
(b) people are an integral part of the system

Question 5.
An institution, where valuable plant material-likely to become irretrievably lost in the wild or in cultivation is preserved in a viable condition is known as
(a) genome
(b) gene library
(c) gene bank
(d) herbarium
Answer:
(c) gene bank

Question 6.
Biological diversity day is
(a) 5^th June
(b) 21^st March
(c) 14^th January
d) 29^th December
Answer:
(d) 29^th December

Question 7.
Biodiversity is determined by
(a) number of individuals in an area
(b) species richness
(c) evenness
(d) Both (b) and (c)
Answer:
(d) Both (b) and (c)

Question 8.
Rare endangered and endemic taxa can be found intact and flourishing in
(a) sacred groves
(b) buffer zone
(c) tropical forests
(d) temperate forests
Answer:
(a) sacred groves

Question 9.
In situ conservation and national genetic resources can be achieved by Establishing
(a) National Park
(b) Wildlife Sanctuaries
(c) Biosphere Reserve
(d) All of a bove
Answer:
(d) All of a bove

Question 10.
IUCN, now called World Conservation Union (WCU) has its headquarter at
(a) South Africa
(b) America
(c) India
(d) Switzerland
Answer:
(d) Switzerland

Question 11.
If forest cover is reduced to half, what is most likely to happen on a long term basis?
(a) Tribals living in these areas will starve to death
(b) Domestic animals in these and joining areas will die due to lack of fodder
(c) Large biomes will become deserts
(d) Crop breeding programmes will suffer due to a reduced ability of variety of germplasm
Answer:
(c) Large biomes will become deserts

Question 12.
The management of biosphere in such a way that it may yield one greatest suitable benefit to present generation, while maintaining its potential to meet the needs of future generation is
(a) conservation
(b) aforestation
(c) fossilization
(d) over-exploitation
Answer:
(b) aforestation

Question 13.
The first Biosphere Reserve establish in India for conserving the gene pool of flora and fauna and the life style of tribals is
(a) Nilgiri Biosphere Reserve
(b) Nandadevi Biosphere Reserve
(c) Uttarakhand Biosphere Reserve
(d) Great Nicobar Biosphere Reserve
Answer:
(a) Nilgiri Biosphere Reserve

Question 14.
The government of India in 1980s has introduced a concept to work closely with the local communities for protecting and managing forests. The concept is
(a) forest research institutes
(b) panel of local communities for forest management
(c) joint forest management
(d) jhum cultivation
Answer:
(c) joint forest management

Question 15.
The percentage of forest cover recommended by the national forest policy (1988)is
(a) 33% for plains and 67% for hills
(b) 37% for plains and 63% for hills
(c) 20% for plains and 70% for hills
(d) 23% for plains and 77% for hills
Answer:
(a) 33% for plains and 67% for hills

Question 16.
The species diversity is maximum in
(a) Western Ghats
(b) Eastern Ghats
(c) Alpine meadows
(d) wetlands.
Answer:
(a) Western Ghats

Question 17.
According to the IUCN (2004), the number of species on the earth that dominates
(a) plants
(b) animals
(c) bacteria
(d) plants
Answer:
(b) animals

Question 18.
The greatest biodiversity in world is reported in
(a) Amazonian forest
(b) coniferous forest
(c) W ghats
(d) Scandinavian forest
Answer:
(a) Amazonian forest

Question 19.
Tropical environments are less seasonal and constant that lead to a greater species diversity, it is come under
(a) niche specialization
(b) species richness
(c) genetic erosion
(d) genetic equilibrium
Answer:
(b) species richness

Question 20.
The equation log S = log C +Z log A represent
(a) species richness and area
(b) genetic diversity and area
(c) allelic frequency and speciation
(d) none of the above
Answer:
(a) species richness and area

Question 21.
The extinction of Steller’s sea cow is due to
(a) overexploitation
(b) alien species invasion
(c) habitat loss and fragmentation
(d) co extinctions
Answer:
(a) overexploitation

Question 22.
The major cause of reduction in biodiversity is due to
(a) habitat fragmentation
(b) overexploitation
(c) overproduction
(d) both a and b
Answer:
(d) both a and b

Question 23.
The introduction of fish that is more serious threat to the indigenous catfishes in river, they are
(a) hilsa
(b) Clarias
(c) carp
(d) catla
Answer:
(b) Clarias

Question 24.
If two species are in obligatory relationship, the extinction of one species affect the other. This is called
(a) competitive exclusion
(b) competitive release
(c) co extinction
(d) co evolution
Answer:
(c) co extinction

Plus Two Zoology Biodiversity and Conservation SCERT Sample Questions and Answers

Question 1.

1. Arrange the following terms into two based on the mode of biodiversity conservation. Hot spots, Zoological Park, Sacred groves, wild life Safari Parks (2)
2. Fill in the blank box noted as A. (1)

Answer:

1. Hotspot and sacred grove Zoological Park and Wild Life Safari Park
2. A. Western ghats

Students can Download Chapter 4 Biotechnology: Principles and Processes Questions and Answers, Plus Two Botany Chapter Wise Questions and Answers helps you to revise the complete Kerala State Syllabus and score more marks in your examinations.

Kerala Plus Two Botany Chapter Wise Questions and Answers Chapter 4 Biotechnology: Principles and Processes

Plus Two Botany Biotechnology: Principles and Processes One Mark Questions and Answers

Question 1.
Ti plasmids used in genetic engineering is obtained from
(a) Bacillus thuringiensis
(b) Agrobacterium tumefaciens
(c) Pseudomonas tumefaciens
(d) Bacillus subtilis
Answer:
(b) Agrobacterium tumefaciens

Question 2.
Which one is regarded as a molecular scissor in biotechnology?
(a) Reverse transcriptase
(b) Restriction endonuclease
(c) Taq polymerase
(d) Topoisomerase
Answer:
(b) Restriction endonuclease

Question 3.
Name the stain used to identify DNA bands in gel electrophoresis
Answer:
Ethidium Bromide

Question 4.
In rDNA technology the alein DNA and cloning vector are a cut by same Restriction endonuclease enzyme. Give reason.
Answer:
The same restriction enzyme must be used cut the alien and foreign DNA forgetting sticky ends.

Question 5.
Name the most common technique is used to transfer DNA into plants.
Answer:
Biolistics or gene gun

Question 6.
The plasmid of Agrobacterium is
(a) Ti plasmid
(b) F1 plasmid
(c) T plasmid
(d) Col E1
Answer:
(a)Ti plasmid

Question 7.
Which of the following is not a restriction endonuclease?
(a) EcoRI
(b) Hind III
(c) pst I
(d) DNAse I
Answer:
(d) DNAse I

Question 8.
The desired DNA can be amplified to 1 billion copies through an important technique. Name it.
Answer:
Polymerace Chain Reaction

Question 9.
Restriction in Restriction enzyme refers to:
(a) Cleaving of phosphodiester bond in DNA by the enzyme
(b) Cutting of DNA at specific position only
(c) Prevention of the multiplication of bacteriophage in bacteria
(d) All of the above
Answer:
(c) Prevention of the multiplication of bacteriophage in bacteria

Question 10.
In PCR technique, nucleotides add one by one on template strand with the help of polymerace enzyme. From which organism it is isolated.
Answer:
Thermus aquaticus

Question 11.
A recombinant DNA molecule can be produced in the absence of the folloiwng:
(a) Resriction endonuclease
(b) DNA ligase
(c) DNA fragments
(d) E.coli
Answer:
(d) E.coli

Question 12.
In agarose gel electrophoresis, DNA molecules are separated on the basis of their:
(a) Charge only
(b) Size only
(c) Charge to size ratio
(d) All of the above
Answer:
(b) Size only

Question 13.
Which of the following bacteria is not a source of restriction endonuclease?
(a) Haemophilus influenzae
(b) Esherichia coli
(c) Agrobacterium tumefaciens
(d) Bacillius amyloli
Answer:
(a) Haemophilus influenzae

Question 14.
Which of the following steps are catalysed by Taq polymerase in a PCR reaction?
(a) Denaturation of template DNA
(b) Annealing of primers to template DNA
(c) Extenstion of primer end on the template DNA
(d) All of the above.
Answer:
(c) Extenstion of primer end on the template DNA

Question 15.
An enzyme catalysing the removal of nucleotides from the ends of DNA is:
(a) endonuclease
(b) exonuclease
(c) DNA ligase
(d) Hind-ll
Answer:
(b) exonuclease

Question 16.
Polymerase Chain Reaction helps in
(a) DNA synthesis
(b) DNA amplification
(c) Protein synthesis
(d) Aminoacid synthesis
Answer:
DNA synthesis

Question 17.
Starting from double stranded DNA suggest a strategy for obtaining large amounts of pure single stranded DNA for sequencing purpose.
Answer:
PCR (POLYMERASE CHAIN REACTION)

Question 18.
The cutting of DNA at specific locations became possible with the discovery of ensymes called ‘molecular scissors’. Identify this enzyme.
Answer:
Restriction enzymes/Restriction Endonucleases

Question 19.
Which among the following is the first discovered Restriction Endonuclease?
(a) Hindi I
(b) Hindi II
(c) EcoR I
(d) EcoR II
Answer:
(b) Hind II

Question 20.
Observe the following illustration and find out the enzymes which are denoted as A and B.
Answer:

1. Restriction endonucleases
2. DNAIigases

Question 21.
Write the technique used for the separation of DNA fragments.
Answer:
Gel Electrophoresis

Question 22.
Final step of gel electrophoresis of DNA molecules from the gel. What is this process called?
Answer:
Elution

Question 23.
One of the given options is not related to PCR. Find it.
(a) Denaturation
(b) Spooling
(c) Extension
(d) Annealing
Answer:
Spooling

Question 24.
Which among the following is not a gene transfer method?
(a) Microinjection
(b) Disarmed pathogen vectors
(c) Gene gun
(d) Elution
Answer:
(d) Elution

Question 25.
Cloning vector suitable for gene transfer in plants is
(a) Ti plasmid
(b) Bacteriophages
(c) Viruses
(d) Transposons
Answer:
(a) Ti Plasmid

Question 26.
Which among the following are the selectable markers of PBR-322.
(a) amp^R, kan^R
(b) tet^R, kan^R
(c) ampR, tetR
(d) chl^R, tet^R
Answer:
ampR, tetR

Question 27.
Restriction Endonucleases cut DNA at specific locations by breaking_______
(a) Sugar-phosphate bonds
(b) Sugar-Nitrogen base bonds
(c) Hydrogen bonds
(d) Disulphide bonds
Answer:
Sugar-phosphate bond

Question 28.
Downstream processing is the final step in the process of recombinant DNA technology. What do you understand by “down stream processing”?
Answer:
Separation and purification of gene product.

Question 29.
Ti plasmid is a suitable cloning vector for plants. It is the plasmid of a bacterium called_______.
Answer:
Agrobacterium tumifaciens.

Plus Two Botany Biotechnology: Principles and Processes Two Mark Questions and Answers

Question 1.
Elution is a major step of electrophoresis.

1. Explain the process.
2. Give the importance of UV light

Answer:

1. Separated bands of DNA are cut from Agarose gel piece and extracted out.
2. Under UV light DNA bands are observed as orange colour.

Question 2.
Genetic engineering is the gene manipulation technique that helps to create new organism with desired genetic make up

1. Give the contribution of Stanley cohen and Herbert Boyer in genetic engineering.
2. Name the enzyme used to cut DNA strand?

Answer:

1. Herbert Boyer and Stanley cohen constructed first recombinant DNA by linking a gene encoding antibiotic resistance with a native plasmid of Salmonella typhimurium in 1972.
2. Restriction endonuclease

Question 3.
Mosquitoes are considered as vectors which transfer the malarial parasite into human body. Plasmids are considered as Vectors in biotechnology’. Justify.
Answer:
Vectors are agents which transfers materials from one organism to another. Plasmids are extra chromosomal DNA seen in bacteria which have the ability for independent replication.

In the field of Biotechnology plasmids are used as vectors as they replicate rapidly after integrating a foreign DNA. Thus, through the plasmid the alien gene can be introduced into another organism.

Question 4.
Eco R I is the restriction endonuclease enzyme obtained from E.coli bacteria that helps them to restrict the growth of virus. What are the criteria for naming endonucleases.
Answer:
EcoRI comes from the name of bacterium Escherechia coli Ry 13. E represents the genus, co represents species, ‘R’ is derived from the name of strain and I is the order in which the enzyme is isolated.

Question 5.
Separation and isolation of DNA fragments can be done by a technique known as gel electrophoresis

1. What is the procedure used separate DNA fragements?
2. Name the organism from which agarose gel is isolated

Answer:
1. Negatively changed DNA fragments are separated by forcing them to move towards the anode under an electric field through agarose matrix.

The DNA fragments separate according to their size in agarose gel. So the smaller the fragment size moves farther. Then it is cut out from the agarose gel by elution.

2. Seaweeds.

Question 6.
PCR is meant for making the multiples copies of the gene of interest.

1. Give the major step involved in PCR.
2. Name the thermostable DNA polymerase enzyme is used in this technique. Why?

Answer:
1. The major step involved in PCR:

• Denaturation – It involves the separation of DNA strands
• Annealing – The double strands are synthesised from free nucleotides by the action of DNA polymerase.
• Extension – The length of the strands are increased as a result of addition of more and more nucleotides. Thus DNA amplified up to 1 billion copies.

2. Taq polymarase
PCR cylinderworks at high temperature. Hence thermostable enzyme is used.

Question 7.
In r DNA technology recombinant DNA is directly injected into the plant cell

1. Name the technique used
2. What you meant by competent host?

Answer:

1. Biolispics or Gene gun.
2. This is done by treating them with calcium ions and incubating the cells and recombinant DNA on ice, followed by placing them at 42°C. Then putting them back on ice. This helps the bacteria to take up the recombinant DNA.

Question 8.
If RNA use, protease, cellulase etc. are not used in the isolation of genetic materials.

1. Find out the difficulties arise during the process of rDNA technology.
2. What is spooling?

Answer:

1. If the above said enzymes are not used, it is difficult to get DNA in pure form for foreign gene isolation.
2. Fine thread of DNA separated out from chilled alcohol.

Question 9.
How is the action of Exonuclease different from that of endonuclease?
Answer:
Exonuclease removes the nucleotides from the ends of DNA molecules while endonuclease takes cut at specific position within a DNA molecule.

Question 10.
Spooling is one of the important method used in r DNA technology.

1. Name the medium in which DNA appear as fine threads.
2. What is the aim of using lysozyme in the isolation of genetic material?

Answer:

1. Chilled alcohol
2. It helps to remove the cell wall of bacteria

Question 11.
Sticky ends are unpaired strands of DNA get by using restriction endonuclease enzyme.
Do you agree?.Give reason
Answer:
Yes. The same restriction enzyme is used to cut both vector DNA and foreign DNA, get sticky ends that facilitate the action of DNA ligase.

Question 12.
In biotechnology lab Ramu interested in constructing r DNA, for this he used tools of r DNA technology.

1. What happen if DNA polymerase enzyme is not used?
2. Name the sequence of DNA subjected to the action of restriction enzyme

Answer:

1. Addition of nucleotides not take place
2. Palindromic sequence

Question 13.
3′ end of template strand is very important in polymerase chain reaction

1. Name the complementary strand that attaches template sequence of 3′ end
2. Find out the type of nucleotides supplied in this technique

Answer:

1. Primer
2. dCTP, d ATP, d GTP, d TTP

Question 14.
In r DNA technology recombinant DNA is directly injected into the plant cell

1. Name the technique used
2. Can you explain two other methods for gene transfer?

Answer:
1. Microinjection.

2. Methods for gene transfer:

a. The bacterium is treated with divalent cation such as calcium which makes the bacterial cell competent to take up DNA (the pores bacterial cell wail is widened).

The recombinant DNA is forced in to the cell by incubating cells with recombined DNA on ice followed by heat shock (42YC) and then back on ice. This helps the bacteria to take up recombined DNA.

b. High velocity micro particles of gold or tungsten is coated with DNA & bombarded into the cell. This method is called biolistics or gene gun.

Question 15.
A researcher in biotechnology is in need to produce insulin in large amounts as part of his study.

1. Which instrument will he select for the purpose?
2. What are the facilities in the instrument?

Answer:
1. Bioreactor.

2. A bioreactor commonly use a stirring type. It consists of cylindrical tank with a stirrer which facilitate mixing of the content of the reactor. It also facilitate oxygen availability.

An agitator system, an oxygen delivery system, temperature control system, pH control system are present in a bioreactor. Small volumes of the products are removed through sampling ports periodically.

Question 16.
In r DNA technology amplification of genetic material is important, In such a device

1. Thermostable enzyme must be used why?
2. Name it.

Answer:

1. The working of programmed cylinder for PCR requires high temperature . Hence thermostable DNA polymerase is used
2. Taq polymerase

Question 17.
It is difficult to use other bacteria instead of Agrobacterium for the transfer of desired gene into plants. Do you agree? Give reasons.
Answer:
Yes. Agrobacterium possess Ti plasmid , it has the ability to transfer gene into dicot plants through infection. Hence it is widely used in gene transfer.

Question 18.
When chromogenic substrate is added to the medium containing bacterial colonies are subjected to insertional inactivation, some appears as blue coloured and others as white coloured colonies. Give reasons.
Answer:
The colonies appears as blue coloured does not possess for eigengene they are called non-recombinants while the colonies of white coloured have foreign gene insert, they are called as recombinants.

The production of blue colour is due to the reaction between beta-galactosidase enzyme and chromogenic substrate while the white coloured colonies have no enzyme for reaction with substrate.

Question 19.
Even though salmonella, Ecoli etc. contains plasmids PBR 322 is widely used in genetic engineering. Why?
Answer:
The plasmid PBR 322 is artificial cloning vector, it possess several features such as origin of replication, selectable marker, cloning sites etc. Some features of artificial cloning vector is not found in natural plasmid. Hence PBR 322 is widely used in genetic engineering.

Question 20.
What you meant by selectable marker? Give 2 examples.
Answer:
The selectable marker is antibiotic resistant gene. Examples are ampicilin resistant and tetracycline resistant gene.

Question 21.
If RNA ase, protease, cellulaseetc are not used in the isolation of genetic materials. Find out the difficulties arise during the process of rDNA technology.
Answer:
If the above said enzymes are not used, it is difficult to get DNA in pure form for foreign gene isolation.

Question 22.
DNA is a hydrophilic molecule, so it can’t pass through the cell membrane. How can DNA inserted into a Bacterial cell?
Answer:
Bacterial cells must have to be competent to take up DNA. This is done by treating them with calcium ions and incubating the cells and recombinant DNA on ice, followed by placing them at 42_oC Then putting them back on ice. This helps the bacteria to take up the recombinant DNA.

Question 23.
State principle underlying gel electrophoresis and mention two applications of this technique in biotechnology.
Answer:
The molecular separation in gel electrophoresis are based on gel filtration as well as electrophoretic mobilities of the molecules being separated. It is among the most powerful and yet conveniently used method of macro molecular separation.

Question 24.
How has Agrobacterium tumifaciens has been suitably modified to act as cloning vector?
Answer:
Genes are transferred from bacterium or virus to eukaryotic cells and these genes force the transformed cell to works at their will eg: Agrobacterium-mediated gene transfer.

Question 25.
How is the action of Exonuclease different from that of endonuclease?
Answer:
Exonuclease removes the nucleotides from the ends of DNA molecules while endonuclease takes cut at specific position within a DNA molecule.

Question 26.
According to the size and charge of DNA sequence that move in an agarose gel,the smaller fragment is selected for cloning

1. Name the technique is used to’separate digested and undigested fragments
2. Which is the method used to get pure DNA fragment from agarose gel

Answer:

1. Gel electroforesis
2. Elusion

Question 27.
Why is the enzyme cellulose used for isolating genetic material from plant cells but not for animal cells?
Answer:
Due to the presence of cell wall in plants cellulose is used, whereas the animal cell lacks cell wall.

Question 28.
Following is the sequence of nucleotide in two strands of DNA .observe the strands and answer the preceding questions
5’ GAATTC 3’
3’ CTTAAG 5’

1. Name the special term used for such an arrangement of nucleotide
2. Name the special type of enzyme which work/function at this specific points
3. Name the enzyme that cut DNA between GA sequence.
4. Name the single strands produced after the action of the enzyme.

Answer:

1. Palindromes
2. Restriction endonucleases
3. E co Rl
4. Sticky strands

Question 29.
DNA cutting enzymes are mainly isolated from prokaryotes

1. Do eukaryotic cells have restriction endonucleases?
2. Justify your answer.

Answer:

1. No.
2. They do not have restriction endonucleases. The eukaryotic cells have some other means of defence against viral infection, i.e., immune system.

Question 30.
Give an example of micro organisms that have transforming ability.
Answer:
A bacterium Agrobacterium tumefactions has T- DNA in its Ti-plasmid which is able to transform normal plant cells to tumour cell and cause crow gall tumours in plants.

Question 31.
‘One of the limitations of traditional hybridization is that it leads to inclusion and multiplication of undesirable genes along with the desired genes’. How does genetic engineering help to overcome these limitations?
Answer:
In this method desirable genes/alien gene can be cut and incorporated into plasmid and thus recombinant DNA is prepared . Then introduced into the target organism.

Question 32.
In-gel electrophoresis, we cannot see pure DNA fragments in visible light and without staining. Explain how is it possible to visualize the DNA fragments?
Answer:
Staining the DNA with Ethidium bromide, followed by exposure to UV radiation.

Question 33.
Figure given below is an important technique used in genetic-engineering.

1. Identify the technique.
2. Find out the aim technique.

Answer:

1. Gel electrophoresis
2. Separation of DNA fragments

Question 34.
Match the following columns A and B suitably

A	B
i. Gel Electrophoresis	a. Continuous culture of microorganisms
ii. Microinjection	b. Amplification of genes
iii. Polymerase Chain reaction	c. Separation of DNA fragments
iv. Bioreactor	d. Precipitation of DNA fragments
	e. Direct gene transfer method

Answer:

A	B
(i)	(c)
(ii)	(e)
(iii)	(b)
(iv)	(a)

Question 35.
Given below is the diagram of a cloning vector.

1. Identify the vector
2. What do amp^R and tet^R stand for?

Answer:

1. pBR 322
2. amp^R – ampicillin resistant gene, tet^R tetracyclin resistant gene.

Question 36.
Each restriction endonuclease recognizes a specific palindromic nucleotide sequence in the DNA.

1. What is a palindrome?
2. Give one example.

Answer:

1. Palindrome is a sequence of base pairs that reads same on two strands of DNA molecule
2. 5′ GAATTC 3′
3. 3′ CTTAAG 5′

Question 37.
Given below are some enzymes used for the release of DNA molecules from different types of cells. Lysozyme, chitinase, cellulose. Arrange them suitably in the columns provided below.

Answer:

Plant cells	Cellulase
Bacterial cells	Lysozyme
Fungal cells	Chitinase

Question 38.
Select markers help us in identifying and eliminating non transformed cells during gene cloning. Explain how the gene for beta-galactosidase enzyme works as a selectable marker?
Answer:
When recombinant DNA inserted within the coding sequence of the enzyme beta-galactosidase, the gene for the enzyme production is removed, after this colonies are transferred into growing medium containing chromogenic substrate, non-transformed colonies give blue colour but transformed colonies not give any colour due to insertional inactivation.

Question 39.
In order to force bacteria to take up the plasmid, the bacterial cells must first be made ‘competent’ to take up DNA. Suggest a method to make bacterial cell competent to receive DNA.
Answer:
At first, treat the cell with divalent cation like calcium, which increases the efficiency with which DNA enters the bacterium through pores in the cell wall. Then incubate of cell with rDNA on ice and placing them briefly at 42° C and then putting back to ice.

Question 40.
Multiple copies of the gene of interest is synthesized in vitro using DNA polymerase enzyme.

1. Which are the three steps of the above process?
2. Find out the DNA polymerase enzyme used here.

Answer:

1. Three steps of the above process:

• Denaturation
• Annealing
• Extension

2. Thermostable DNA polymerase/Taq polymerase.

Question 41.
Bioreactors help for the large scale production of recombinant proteins.

1. Which are the two commonly used bioreactors?
2. What is the purpose of stirring mechanism in a bioreactor?

Answer:

1. Simple stirred tank bioreactor
2. Sparged stirred tank bioreactor

The stirrer facilitates mixing of content and o₂ availability.

Question 42.
Given below is the diagram of a cloning vector. Observe the diagram and answer the following questions.

1. Name the bacterium from which this vector is made?
2. What are the significances of ‘ori’ and ‘rop’ denoted in the picture?

Answer:

1. Ecoli
2. “ori”-origin of replication it is the point from which replication starts “rop”- codes for proteins involved in replication of plasmid.

Question 43.
Restriction Endonucleases are enzymes responsible for cutting of DNA molecule. Eco Rl is derived.

1. How the name Eco Rl is derived?
2. Write the palindromic sequence of Eco Rl.

Answer:
1. First letter from the genus and second two letters from the species name Letter ‘R’ is derived from the type of strain Roman number I indicates the order of discovery.

2. 5′ ………..GAATTC 3′
3’…………CTTAAG 5′

Plus Two Botany Biotechnology: Principles and Processes Three Mark Questions and Answers

Question 1.
Write any three uses of Gene cloning.
Answer:

1. Genes of interest can be inserted into animals, so as to produce better farm animals.
2. Desired proteins like insulin, hormones, interferons, vitamins can be manufactured in bacteria on an industrial basis.
3. Recombinant vaccines, improved antibiotics can be produced by gene cloning.

Question 2.

1. Identify the process.
2. Identify the enzymes involved in steps (ii) and (iii)
3. Write the base sequences recognised by EcoRI

Answer:
1. Recombinant DNA technology.

2. enzymes involved in steps:

• Restriction Endonuclease
• Ligase enzyme

3. sequences recognised by EcoRI:

• GAATTC
• CTTAAG

Question 3.
Vehicles which are used to transfer a gene from one cell to another is called a cloning vector. PBR 322 is a widely used cloning vector.

1. Name 2 important features that a cloning vector should possess.
2. What is the importance of Ori?

Answer:

1. Origin of replication Selectable marker
2. Origin of replication the point from which replication begins.

Question 4.
Stanley cohen and Hebert Boyer constructed r DNA by using plasmid and antibiotic-resistant gene.

1. Name the slicing and splicing enzyme used.
2. What is the significance of slicing enzyme in rDNA technology?

Answer:
1. Slicing enzyme – Restriction endo nuclease Splicing enzyme-DNA ligase

2. significance of slicing enzyme in rDNA technology:

• It is used to cut within DNA sequence.
• Same restriction enzyme is used to cut both vector DNA and foreign DNA.

Question 5.
Match the items in column A with the items of Column B.

A	B
Palindromic nucleotide sequence	Separation of DNA fragments
Restriction endonuclease	Synthesise gene product
Gel Electrophoresis	Tool of recombinant technology
Bioreactor	5′ – GAATTC- 3′, 3′ – CTTAAG- 5′
Biolistics	Cloning vector
pBR322	Method to introduce alien DNA into host

Answer:

A	B
Palindromic nucleotide sequence	5′ – GAATTC- 3′, 3′ – CTTAAG- 5‘
Restriction endonuclease	Tool of recombinant technology
Gel Electrophoresis	Separation of DNA fragments
Bioreactor	Synthesise gene product
Biolistics	Method to introduce alien DNA into host
PBR322	Cloning vector

Question 6.
Following is the sequence of nucleotide in two strands of DNA. Observe the strands and answer the preceding questions
5’ GAATTC 3’
3’ CTTAAG 5’

1. Name the special term used for such an arrangement of nucleotide
2. Name the enzyme that cut DNA between GA sequence.
3. Name the single strands produced after the action of the enzyme.

Answer:

1. Palindromes
2. EcoRI
3. Sticky strands

Question 7.
Following are the various steps of recombinant DNA technology. Arrange them in correct sequential order.

i) Obtaining the foreign gene product
ii) Amplification of gene of interest using PCR
iii) Cutting of DNA at specific locations
iv) Downstream processing
v) Intsertion of recombinant DNA into the host cell/organism
vi) Isolation of genetic material
Answer:
vi) Isolation of genetic material
iii) Cutting of DNA at specific locations
ii) Amplification of gene of interest using PCR Insertion of recombinant DNA into the host cell organism
i) Obtaining the foreign gene product
iv) Downstream processing

Plus Two Botany Biotechnology: Principles and Processes NCERT Questions and Answers

Question 1.
From what you have learnt, can you tell whether enzymes are bigger or DNA is bigger in molecular size? How did you know?
Answer:
DNA molecules are bigger in molecular size as compared to molecular size of enzymes. It is because an enzyme (protein) is synthesized from the segment of DNA called gene.

Question 2.
What would be the molar concentration of human DNA in a human cell?
Answer:
In human being the concentration of DNA is 0.4%. It contains 6.6 × 10⁹ bp.

Question 3.
Besides better aeration and mixing properties, what other advantage do stirred tank bioreactors have over shake flasks?
Answer:
Shake flasks are used for growing microbes and mixing the desired materials on a small scale in the lab. But the large scale production of desired bio technological product requires large stirred tank bioreactors. Besides better aeration and mixing properties, the bioreactors have following advantages –

1. It has oxygen delivery system.
2. It has foam control, temperature and P^ control system.
3. Small volumes of culture can be withdrawn periodically.

Question 4.
Do eukaryotic cells have restriction endonucleases? Justify your answer.
Answer:
No. They do not have restriction endonucleases. The eukaryotic cells have some other means of defence against viral infection ie, immune system.

Question 5.
Can you recall meiosis and indicate at what stage a recombinant DNA is made?
Answer:
Pachytene stage of prophase I by crossing over.

Question 6.
Can you think and answer how a reporter enzyme can be used to monitor transformation of host cells by foreign DNA in addition to a selectable marker?
Answer:
Reporter enzyme can differentiate recombinants from non-recombinants on the basis of their ability to produce specific color in the presence of chromogenic substrate. ArDNA is inserted within the coding sequence of the enzyme, galactosidase.

This results into inactivation f the enzyme which is referred to as insertional inactivation. The presence of a chromogenic substrate gives blue colored colonies, if the plasmid in the bacteria does not have an insert.

Presence of insert results into insertional inactivation of the-galactosidase and the colonies do not produce any colour. These are identified as recombinant colonies.

Plus Two Botany Biotechnology: Principles and Processes Multiple Choice Questions and Answers

Question 1.
The linking of antibiotic resistance gene with the plasmid vector became possible with
(a) DNA ligase
(b) Endonucleases
(c) DNA polymerase
(d) Exonucleases
Answer:
(a) DNA ligase

Question 2.
The construction of the first recombinant DNA was done by using the native plasmid of
(a) E.coli
(b) Salmonella typhimurium
(c) Bacillus thuringiensis
(d) yeast
Answer:
(b) Salmonella typhimurium

Question 3.
Which of the following is used as a best genetic vector in plants?
(a) Bacillus thuringiensis
(b) Agrobacterium tumefaciens
(c) Pseudomonas putida
(d) None of the above
Answer:
(b) Agrobacterium tumefaciens

Question 4.
One of the key factors, which makes the plasmid, the vector in genetic engineering?
(a) It is resistant to antibiotics
(b) It is resistant to restriction enzymes
(c) It has the ability to carry a foreign gene
(d) It has the ability to cause infection in the host
Answer:
(c) It has the ability to carry a foreign gene

Question 5.
A clone is
(a) heterozygote obtained asexually
(b) homozygote obtained asexually
(c) heterozygote produced by sexual methods
(d) homozygote produced by sexual methods
Answer:
(b) homozygote obtained asexually

Question 6.
In recombinant DNA technique, the term vector refers to
(a) donor DNA is identified and picked up through eletrophoresis
(b) plasmid, transfers DNA into living cell
(c) collection of entire genome in form of plasmid
(d) enzyme, cuts the DNA at specific sites
Answer:
(b) plasmid, transfers DNA into living cell

Question 7.
The enzyme employed for amplification of DNA during PCR is commercially obtained from
(a) Streptococcus pyogenes
(b) Bacillus licheniformis
(c) Trichodermapallidum
(d) Thermusaquaticus
Answer:
(d) Thermusaquaticus

Question 8.
The enzyme used for annealing the cut DNA segments is
(a) DNA ligase
(b) Helicase
(c) Topoisomerase
(d) Polymerase
Answer:
(d) Polymerase

Question 9.
How does PCR serve the purpose of early diagnosis?
(a) By detecting very low amounts of DNA by amplification
(b) It is a powerful technique to identify man genetic disorders
(c) To detect mutations is genes in suspected cancerpatients
(d) All the above
Answer:
(d) All the above

Question 10.
Enzyme used in the addition of nucleotides in DNA replication is
(a) catalase
(b) DNA polymerase
(c) nuclease
(d) RNA polymrerase
Answer:
(b) DNA polymerase

Question 11.
Importance of restriction endonuclease enzyme is to cut
(a) RNA strands at specific site
(b) DNA strands at specific site
(c) Ends of DNA strands
(d) none of the above
Answer:
(b) DNA strands at specific site

Question 12.
Large amount of recombinant protein is produced in
(a) tissue culture
(b) bioreactor
(c) somatic hybridization
(d) genetic engineering
Answer:
(b) bioreactor

Question 13.
Polymerase enzyme in the replication process to produce 1 billion copies of DNA is
(a) RNA polymerase 1
(b) DNA polymerase 1
(c) DNA polymerase 11
(d) taq polymerase
Answer:
(d) taq polymerase

Question 14.
Digested and undigested fragments of DNA can be observed in elecrophoresis by
(a) Ethidium bromide
(b) CFC
(c) Ethidium chloride
(d) acetyl chloride
Answer:
(a) Ethidium bromide

Question 15.
In which step of DNA amplification DNA hybridization occurs
(a) denaturation
(b) extention
(c) annealing
(d) elongation
Answer:
(c) annealing

Question 16.
The plasimid of Agrobacterium is
(a) Ti plasmid
(b) F1 plasmid
(c) T plasmid
(d) col E1
Answer:
(a) Ti plasmid

Question 17.
The ori of clonimg vector indicates
(a) cloning site
(b) restriction site
(c) replication site
(d) selectable marker site
Answer:
(c) replication site

Question 18.
Selectable marker of cloning vector plays an important role in
(a) identification of recombinants
(b) identification of non recombinants
(c) identification of recombinants from non recombinants
(d) none of the above
Answer:
(c) identification of recombinants from non recombinants

Question 19.
Coating of gold or tungsten particle with DNA is used in
(a) direct gene transfer
(b) indirect gene transfer
(c) both direct and indirect gene transfer
(d) none of the above
Answer:
(a) direct gene transfer

Students can Download Chapter 6 Organisms and Populations Questions and Answers, Plus Two Botany Chapter Wise Questions and Answers helps you to revise the complete Kerala State Syllabus and score more marks in your examinations.

Kerala Plus Two Botany Chapter Wise Questions and Answers Chapter 6 Organisms and Populations

Plus Two Botany Organisms and Populations One Mark Questions and Answers

Question 1.
Zero growth means
(a) Natality balance mortality
(b) Natality is more than mortality
(c) Natality is less than mortality
(d) Natality is zero
Answer:
(a) Natality balance mortality

Question 2.
Different types of interactions and the nature of interactions between species A and B are given in column I and II respectively. Choose the correct answer key where they are matched.

Answer:
(c) 2 5 4 3 1

Question 3.
Which one of the following is not used for construction of ecological pyramids?
(a) Dry weight
(b) Number of individuals
(c) Rate of energy flow
(d) Fresh weight
Answer:
(d) Fresh weight

Question 4.
In a pond there were 200 frogs, 40 more were born in a year. Calculate the birth rate of population.
Answer:
Birth rate = 40/200 = 0.2 offspring per year.

Question 5.
What is the cause of altitude sickness at high altitudes?
Answer:
Is due to the low atmospheric pressure of high altitudes that the body is unable to get enough oxygen.

Question 6.
Amensalism is an association between two species where:
(a) One species is harmed and other is benefitted
(b) One species is harmed and other is unaffected
(c) One species is benefitted and other is unaffected
(d) Both the species are harmed
Answer:
(c) One species is benefitted and other is unaffected.

Question 7.
According to Allen’s Rule, the mammals from colder climates have:
(a) Shorter ears and longer limbs
(b) longer ears and shorter limbs
(c) longer ears and longer limbs
(d) shorter ears and shorter limbs
Answer:
(c) longer ears and longer limbs

Question 8.
Lichens are the association of:
(a) bacteria and fungus
(b) algae and bacterium
(c) fungus and algae
(d) fungus and virus
Answer:
(c) fungus and algae

Question 9.
Salt concentration (Salinity) of the sea measured in parts perthousand is:
(a) 10-15
(b) 30-75
(c)  0-5
(d) 30-35
Answer:
(d) 30-35

Question 10.
Formation of tropical forests needs mean annual temperature and mean annual precipitation as:
(a) 18-25°C and 150-400 cm
(b) 5-15°C and 50-100 cm
(c) 30-50°C and 100-150 cm
(d) 5-15°C and 100-200 cm
Answer:
(a) 18-25°C and 150 – 400 cm

Question 11.
Observe the following statements. Select the correct one.
(a) Temperature increases progressively from equator towards the poles and from plain to mountain tops.
(b) Temperature is sub-zero level in polar areas and high altitude and increases to above 50°c in tropical desert in summer.
(c) In unique habitats such as thermal springs and deep sea hydrothermal vents average temperatures exceed 20°c.
(d) Mango trees grow in temperate countries like Canada and Germany.
Answer:
(a) Temperature is sub-zero level in polar areas and high altitude and increases to above 50°c in tropical desert in summer.

Question 12.
Cuscuta and vanda are growing on a mango tree. Which plant makes harm to the mango tree. Justify your answer.
Answer:
Cuscuta makes harm, it is a parasite that derives its nutrition from the host plant.

Question 13.
Which one of the following is not related to competition.
(a) Competition occurs when closely related species compete for the same resources that are limiting.
(b) Unrelated species also compete for same resources.
(c) Even if resources are abundant, the feeding effect of one species might be reduced due to the interfering and inhibitory presence of other species.
(d) Calotropis. growing in abandoned fields is an example of competition.
Answer:
(d) Calotropis growing in abandoned fields is an example of competition.

Question 14.
Parasitic mode of life ensures free lodging and meals. Identify the correct statements related to parasites.
(a) Parasites are not host specific and co-evolved.
(b) Parasites have special adaptations like loss of unnecessary sense organs, presence of suckers, loss of digestive systems, high reproductive capacity.
(c) Lice is an endoparasite.
(d) The female mosquito is a parasite.
Answer:
a, b.

Question 15.
Observe the relationship between the first two terms and fill in the blanks. Hibernation: Bear;……….: Snail
Answer:
Aestivation.

Question 16.
Read the statements properly and choose the correct one.
(a) Many desert plants have CAM pathway that enables their stomata to remain open during day time.
(b) In Opuntia, leaf reduced into green flattened structure.
(c) Kangaroo rat in North American deserts is capable of meeting all water requirements through the protein oxidation.
(d) Mammals from colder climate generally have shorter ears and limbs.
Answer:
(d) Mammals from colder climate generally have shorter ears and limbs.

Plus Two Botany Organisms and Populations Two Mark Questions and Answers

Question 1.
In a biotic community initially the population size was 250 during the year 2005 after a period of time 130 animals died of forest fire 20 were nearly born. During the next winter season 20 animals immigrated. Find out the change in population size.
Answer:
Nt = No + B + I – D + E
Therefore Nt = 250+ 20+ 20- 130 + 40
= 290- 170= 120

Question 2.
Some organism are different intheirtoleration level to temperature fluctuations

1. Name the type of organism that can tolerate wide range of temperature variation especially in increased global temperature?
2. Name the other type organisms restricted to narrow range.

Answer:

1. Eurythermal species,
2. Stenothermal.

Question 3.
In desert condition water availability very low hence normal plants cannot withstand. What are the adaptations are desert plants.
Answer:

1. Thick cuticle on their leaf surfaces
2. Stomata arranged in deep pits to minimise water loss through transpiration.
3. They show CAM pathway (they open stomata during night and closed during day time)
4. Opuntia, their leaves are reduced to spines and the flattened stems do photosynthesis.

Question 4.
In extreme summer and winter certain animals like frogs and lizard abandon their active life. This is popularly known as summer sleep and winter sleep respectively. Write down the technical term for summer sleep and winter sleep.
Answer:

• Summer sleep – Aestivation
• Winter sleep – Hibernation

Question 5.
What you meant by resource partitioning in an ecosystem.
Answer:
If two species compete for the same resource, they avoid competition by choosing different times for feeding or different foraging patterns.This is called resource partitioning.

Question 6.
Camouflaging is a method adopted by prey to lessen effect of predatien in animals. List out some mechanisms seen in plant species.
Answer:
Plants have evolved a variety of morphological and chemical defences against their predators (herbi-vores).

1. Thorns in plants are morphological means of defence.
2. Plants produce and store chemicals that make the herbivore sick. Eg: Glycosides, Quinine, Caf¬feine, Opuim etc.

Question 7.
Gause proposed the Competitive Exclusion Principle in 1934.

1. Define it
2. Give an example.

Answer:
1. Competitive Exclusion Principle states that the closely related species competing for the same resources cannot co-exist indefinitely The competitively inferior one will be eliminated eventually.

2. Abingdon tortoise compete with goats in galapagos island for same food source and tortoise became extinct.

Question 8.
Many tribes living in high altitudes of Himalayas have higher red blood cell count.

1. Do you agree?
2. Give reason

Answer:
1. Yes.

2. In high altitudes there is low oxygen availability. The tribes having high RBC production since the binding capacity of RBC with 02 decreases and ultimately results in high breathing rate.

Question 9.
Tribalsin high altitude are difficult to live in the initial phase of colonization but after few days they are adapted to live.

1. Write down 2 adaptations they developed
2. Name two disease symptoms in low 02 and atmospheric pressure conditions

Answer:
1. 2 adaptations they developed:

• increase RBC production
• increase breathing rate

2. nausea, fatigue.

Question 10.
The relationship between cattle egret and grazing cattle is considered as commensalism. Justify.
Answer:
Cattle egret gets food in the form of insects when the grazing cattle flushes out insects from the vegetation as it moves during grazing. The egret is benefited but there is no harm for the cattle.

Question 11.
Abingdon tortoise and goats are compete with each other in Galapagos Islands for common food finally one of them is eliminated.

1. Name the principle proposed by Gause to explain the elimination of one species due to other
2. Suggest one important method to reduce competition

Answer:

1. competitive exclusion principle
2. resource partitioning

Question 12.
Thermoregulation is expensive to small animals like Shrews and Hummingbirds live in colder climates. Do you agree? Give reason.
Answer:
Yes
Their body surface area is large compared to body volume, hence they have to spend more energy to increase metabolic rate when cold outside for producing more heat.

Question 13.
Ophrys is a Mediterranean orchid it’s petals shows resemblance to female be in colour size and markings but a male bee come into the flower and pollinate

1. Name the sexual deciet between male bees and orchid
2. Which is the interaction used to explain pollination method mentioned above

Answer:

1. pseudocopulation
2. mutualism

Question 14.
In sample A population growth under abandoned food supply violin sample B population growth under reduced food supply.

1. Name the two types of growth occurs in sample A and sample B
2. What will be the shape of curve get in sample A and sample B population

Answer:

1. In sample A exponential growth, in sample B Logistic growth
2. In sample A- J shaped, In sample B- S shaped

Question 15.
dN/dt = (b-d) × N
Let (b-d) = r, then
dN/dt = rN

1. What does r indicate in the above equation?
2. Which parameter is chosen for assessing impact of any biotic or abiotic factor on population growth?

Answer:

1. Intrinsic rate of natural increase
2. r parameter

Question 16.
Use proper terms of the statement given below.

1. Few organisms can tolerate and thrive in wide range of temperature.
2. Some organisms are tolerant to a narrow range of salinities.
3. The organism should try to maintain the constancy of its internal environment.
4. The organism may move temporarily from the stressful habitats to more hospitable area and return when stressful period is over.

Answer:

1. Eurythermal
2. Stenothermal
3. Homeostasis
4. Migrate

Question 17.
The integral form of the exponential growth equation is Nt = N₀e^rt. Expand the symbols in this equation.
Answer:

• Nt – Population density at time t
• No – Population density at time 0
• r – Intrinsic rate of natural increase
• e – base of natural logarithms.

Question 18.
In rocky intertidal communities of the American Pacific Coast the starfish Pisasterwere removed for an experimental purpose.

1. How did this affect the invertebrates in that region?
2. List out the important role of predators in nature.

Answer:
1. Pisaster is an important predator in the intertidal area. When Pisasters were removed, more than 10 invertebrate species became extinct because of interspecific competition.

2. important role of predators in nature:

• Predation helps to transfer energy to higher trohpic level from plants,
• Agricultural pest control or biological control is based on the ability of predator that important in regulating prey population.

Question 19.
Match A with B based on mutualism.

A	B
Lichen	Wasp
Mycorrhiza	Ophrys
Fig tree	Cyanobacteria
Sexual deceit	Fungi

Answer:

• Lichen – cyanobacteria
• Mycorrhiza – fungi
• Fig tree – Wasp
• Sexual deceit – Ophrys

Question 20.
Define commensalism and write any two examples.
Answer:
Interaction in which one species benefited and the other is neither harmed nor benefited.
Example – Cattle egret and grazing cattle Sea anemone and clownfish.

Question 21.
Adaptations may be morphological, physiological or behavioural. Write the behavioural adaptations in desert lizard.
Answer:
Desert lizards bask in the sun and absorb heat when their body temperature drops below the comfort zone They move into shade when the temperature starts increasing.

Question 22.
Interaction between sea anemone and clown fish is termed as commensalism. Substantiate this statement.
Answer:
Sea anemone has stining tentacles and the clown fish lives among them, In this interaction the fish get protection from predators which stay away from the stinging tentacles but sea anemone does not derive any benefit or harm by hosting the clown fish.

Question 23.
Competition causes extinction of species. Substantiate this statement based on the extinction of Abingdon tortoise.
Answer:
A bingdon tortoise in Galapagos islands became extinct due to the introduction of goat on the island because goats have greater browsing efficiency than tortoise. Due to the lack of food tortoise became extinct.

Plus Two Botany Organisms and Populations Three Mark Questions and Answers

Question 1.
Given below is the bar diagram showing the age structure of three countries. Answer the following questions by analyzing the diagram.

1. Which country has the highest population?
2. Which country has declining population?
3. One of the countries has a stable population. Explain.

Answer:

1. A has the highest population
2. C has declining population
3. B has stable population. In this population reproductive and pre-reproductive individuals are more or less same. Hence it is stable.

Question 2.
Population growth curves (two types are given: observing the graph answer the following questions).

1. Identify the curves a & b.
2. Explain the signficance of K.
3. Which population growth has limited food supply?

Answer:

1. Curve ‘a’ is exponential growth curve and b is logistic growth curve.
2. K is the carrying capacity. Beyond K no further growth of population is possible.
3. Logistic growth

1. Name A, B and C pyramids.
2. Which one is ideal for a population. Suggest reason.
3. How does such age pyramids help policy makers of the country.

Answer:
1. Name A, B and C pyramids:

• Expaning
• Stable
• Declining

2. Expanding
Pre reproductive individuals are more in number than reproductive and post-reproductive.

3. It reflects the growth status

Question 4.
Scientist paul Ehrlich and Peter Raven developed the concept of co-evolution.

1. Give an example for co-evolution.
2. How did they show mutualistic association.
3. Name the mutualistic relationship shown by male bee and ophrys petal.

Answer:
1. Wasp and fig tree.

2. The female wasp lays its egg in the ovary locule and uses the developing seeds within the fruit for nourishing its larvae. The wasp pollinates the fig inflorescence while searching for suitable egg laying sites.

3. Pseudocopulation

Question 5.
Analyze the given graph which represents the population growth curve.

1. Which growth curves do ‘a’ and ‘b’ indicate?
2. Suggest an equation for ‘b’.
3. What parameters are required for calculating current r-value?

Answer:
1. growth curves do ‘a’ and ‘b’ indicate

• Exponential growth curve
• logistic growth curve

2. \(\frac{\mathrm{d}\mathrm{N}}{\mathrm{dt}}=\mathrm{rN}\left(\frac{\mathrm{K}-\mathrm{N}}{\mathrm{K}}\right)\)

3. Current birth rate and death rate.

Question 6.
Observe the flow chart given below and answer the following questions.

1. Identify I, B, D and E.
2. Write the equation for population density.
3. B and I are positive, D and E are negative about population. Suggest reason.

Answer:
1. Identify I, B, D and E:

• l-Immigration
• D-Mortality
• B-Natality
• E-Emigration

2. N_t+1 = Nt + [(B+1)-(D + E)]

3. N and I are natality and immigration – Both contribute an increase in population density. D and E are mortality and emigration – Both contribute to decrease in population.

Question 7.
Analyse the given graph and answer the following questions.

1. Label a, b, c.
2. How a differs from b?

Answer:
1.

• Conformers
• Regulators
• Partial regulators

2.

• Organism Cannot maintain constant internal environment.
• Organism can maintain constant internal environment through thermoregulation and osmoregulation.

Question 8.
Fill in the blanks.

Answer:
(a) Mutualism
(b) Competition
(c) Predation
(d) Parasitism
(e) Commensalism
(f) Amensalism

Plus Two Botany Organisms and Populations NCERT Mark Questions and Answers

Question 1.
Define phenotypic adaption. Give one example.
Answer:
Phenotypic adaptions are acquired non-genetic changes in individuals such as physiological modification, acclimatization or behavioural changes.

For examples, if a person has ever been to any high altitude, on visiting such as place he or she must have altitude sickness because body does not get enough oxygen. But gradually he or she gets acclimatized and stop experiencing altitude sickness.

Question 2.
Most living organisms cannot survive at temperature above 45°C. How are some microbes able to live in habitats with temperature exceeding 100°C?
Answer:
The microbes of high temperature area are known as thermo-acidophiles. They are able to survive at high temperature through.

1. Reduction in amount of free water.
2. Occurrence of branched chain lipids that reduce fluidity of cell membranes.

Question 3.
List the attributes that populations but not individuals possess.
Answer:

• Population density.
• Natality or birth rate.
• Mortality or death rate.
• Population growth.
• Sex ratio.
• Age distribution.

Question 4.
If a population growing exponentially double in size in 3 years, what is the intrinsic rate of increase (r) of the population?
Answer:
N_t = N₀ e^rt
Since N_t = 2; N0 = 1, e = 2.71828 ; t = 3
2 = (1 × 2.71828)^3r
Log 2 = 3 r log (2.71828)
0.3010 = 3 r × 0.4343
r= 0.2310
Intrinsic rate of increase=23.1 %.

Question 5.
Name important defence mechanisms in plants against herbivory?
Answer:
Leaves modified into thorns, development of spiny margins on the leaves. Many plants produce and store chemicals that make the herbivore sick.

eg: calotropis produces highly poisonous cardiac glycosides. Some other chemical substances like nicotine, quinine, opium etc are produced by plants and provide defence against grazing animals.

Question 6.
An orchid plant is growing on the branch of mango tree. How do you describe this interaction?
Answer:
It is an example of commensalism, where the or-chid gets space (benefitted) but the mango tree is neither benefited nor harmed.

Question 7.
What is the ecological principle behind the biological control method of managing with pest insects?
Answer:
The ecological principle behind the biological control of pest insects is based on the ability of predator to regulate prey population in that habitat. For example Gambusia fish prey upon the larvae of mosquito and acts as biological controller of malaria.

Plus Two Botany Organisms and Populations Multiple Choice Questions and Answers

Question 1.
The niche of a population is defined as
(a) set of condition that interacts
(b) place where it lives
(c) set of conditions and resources it uses
(d) geographical’ area that it covers
Answer:
(c) set of conditions and resources it uses

Question 2.
Competition for food, light and space is most severe between two
(a) closely related species growing in different niches
(b) distantly related species growing in different niches
(c) closely related species growing in same niches
(d) distantly related species growing in same niches
Answer:
(c) closely related species growing in same niches

Question 3.
An ecosystem, which can be easily damaged but can recover after some time if damaging effect stops, will be having
(a) low stability and high resilience
(b) high stability and low resilience
(c) low stability and low resilience
(d) high stability and high resilience
Answer:
(a) low stability and high resilience

Question 4.
Assertion :Predaton is an interspecific ineraction with I a feeding strategy.
Reason : Predation and their prey maintain fairly stable population become abundant or scarce.
(a) Both Assertion and Reason are true and Reason is the correct explanation of Assertion
(b) Both Assertion and Reason are true but Reason is not the correct explanation of Assertion
(c) Assertion is true but Reason is false
(d) Both Assertion and Reason are false
Answer:
(b) Both Assertion and Reason are true but Reason is not the correct explanation of Assertion

Question 5.
The assemblage of all the populations of different species that function as an Integrated unit through coevolved metabolic transformation in a specific area is Called
(a) biome
(b) biotic community
(c) population
(d) ecosystem
Answer:
(b) biotic community

Question 6.
A lake near a village suffered heavy mortality of fishes within a few days. Consider the following reasons for this
I) Lots of urea and phosphate fertilizers were used in the crops in the vicinity.
II) The area was sprayed with DDT by an aircraft
III) The lake water turned green and stinky.
IV Phytoplankton populations in the lake declined initially thereby greatly reducing photosynthesis. Which two of the above were the main causes of fish mortality in the lake?
(a) II, III
(b) III, IV
(c) I, III
(d) I, II
Answer:
(d) I, II

Question 7.
In commensalism
(a) both partners are harmed
(b) weaker partner is benefitted
(c) both partners are benefitted
(d) None of the partners is benefited
Answer:
(b) weaker partner is benefitted

Question 8.
If the strong partner is benefitted and the weak partner is damaged. It is known as
(a) predation
(b) alleloathy
(c) symbiosis
(d) commensalisms
Answer:
(a) predation

Question 9.
Competition of species leads to
(a) extinction
(b) mutation
(c) greater number of niches are formed
(d) symbiosis
Answer:
(a) extinction

Question 10.
Which of the following statement regarding species interdependence are true?
I. An association of two species where one is benefitted and other remain unaffected is called mutualism.
II. An interspecific association where both partners derive benefit from each other is called commensalism.
III. A direct food relation between two species of animals in which one animals kills and feeds on another is referred as predation.
IV. A relationship between two of organisms where both the partners are benefitted from each other is called symbiosis.
(a) I and II only
(b) III and IV only
(c) I and III only
(d) II and III only
Answer:
(b) III and IV only

Question 11.
In India, human population is heavily weighed towards the younger age group as a result of
(a) Short life span of many individuals and low birth rate
(b) Short life span of many individuals and high birth rate
(c) long life span of many individuals and high birth rate
(d) long life span of many individuals and low birth rate
Answer:
(b) Short life span of many individuals and high birth rate

Question 12.
Ratio between mortality and natality is
(a) population ratio
(b) census proportion
(c) vital index
(d) density coefficient
Answer:
(c) vital index

Question 13.
The population of an insect species shows an explosive increase in number during rainy season followed by its disappearance at the end of the season. What does this show?
(a) S-shaped or sigmoid growth of this insect
(b) The food plants mature and die at the end of the rainy season
(c) Its population growth curve is of type
(d) The population of its predators increases enormously
Answer:
(c) Its population growth curve is of type

Question 14.
The annual variations in temperature results distinct seasons, these variations together with annual variation in precipitation leads to
(a) rain forest
(b) deserts ,
(c) lake
(d) both a and b
Answer:
(d) both a and b

Question 15.
Few organisms can tolerate and thrive in a wide range of temperatures they are called as
(a) eurythermal
(b) stenothermal
(c) euryhaline
(d) stenohaline
Answer:
(a) eurythermal

Question 16.
The type of benthic animals in ocean is determined by
(a) pH of water
(b) mineral composition
(c) sediment characteristics
(d) dissolved CO„ level
Answer:
(c) sediment characteristics

Question 17.
Important characteristics of mammals live in Antarctica or in the Sahara desert have
(a) osmoregulation
(b) thermoregulation
(c) thermoperiodicity
(d) both a and b
Answer:
(d) both a and b

Question 18.
The Smaller animals have a larger surface area, so they tend to lose body heat very fast when it is cold outside. This result in spending
(a) much energy for catabolism
(b) much energy for catabolism and anabolism
(c) low energy for catabolism
(d) much energy for anabolism
Answer:
(b) much energy for catabolism and anabolism

Question 19.
The Keolado National Park in Rajasthan host many
(a) bat population from warmer countries
(b) bird population from warmer countries
(c) bird population from winter countries
(d) bat population from winter countries
Answer:
(c) bird population from winter countries

Question 20.
Mammals of colder climates have shorter ears and limbs to minimise heat loss. This is come under
(a) Allen’s Rule
(b) bergmans rule
(c) jordans rule
(d) none of the above
Answer:
(a) Allen’s Rule

Question 21.
The number of births plus the number of immigrants is the major component in determining the
(a) density of population
(b) sex ratio
(c) age distribution
(d) species composition
Answer:
(a) density of population

Question 22.
If the resources in the habitat are unlimited, this results in the population have
(a) s- shaped curve
(b) j shaped curve
(c) parabolic curvature
(d) linear curve
Answer:
(b) j shaped curve

Question 23.
The equation dN/dt = rN(K-N/K) is represented as
(a) logistic population growth
(b) exponential population growth K
(c) Verhulst-Pearl Logistic Growth
(d) both a and c
Answer:
(d) both a and c

Students can Download Chapter 7 Microbes in Human Welfare Questions and Answers, Plus Two Zoology Chapter Wise Questions and Answers helps you to revise the complete Kerala State Syllabus and score more marks in your examinations.

Kerala Plus Two Zoology Chapter Wise Questions and Answers Chapter 7 Microbes in Human Welfare

Plus Two Zoology Microbes in Human Welfare One Mark Questions and Answers

Question 1.
Which of the following plants is used as biofertilizer?
(a) Nostoc
(b) Funaria
(c) Volvox
(d) Rhizopus
Answer:
(a) Nostoc

Question 2.
Bacillus thuringiensis (Bt) strains have been used for designing novel
(a) bio-metallurgical technique
(b) bio-mineralisation processes
(c) bio-insecticidal plants
(d) bio-fertilizers
Answer:
(c) bio-insecticidal plants

Question 3.
Cyclosporin A obtained from
(a) bacteria
(b) fungi
(c) nematode
(d) virus
Answer:
(b) fungi

Question 4.
Swiss cheese’ with large holes are due to production of a large amount of CO₂ by a bacterium named
(a) Propionibacterium sharmanii.
(b) Penicillium notatum
(c) Streptococcus
(d) Monascus purpureus
Answer:
(a) Propionibacterium sharmanii

Question 5.
Clostridium butylicum produces
(a) butyric acid
(b) acetic acid
(c) aspartic acid
(d) lactic acid
Answer:
(a) butyric acid

Question 6.
Note the relationship between first two words and suggest suitable word for the fourth place. Acetobacter aceti – acetic acid, Aspergillus niger – ……..acid.
Answer:
(a) Citric acid

Question 7.
Masses of bacteria associated with fungal filaments to form mesh-like structures in secondary treatment in sewage plants. What is it called?
Answer:
Floes

Question 8.
Biogas is a terminology that we hear in our day to day life. Name the gases produced in biogas plant.
Answer:
Methane, CO₂, H₂

Question 9.
………..Is called brewer’s yeast, which is used for fermenting malted cereals and fruit juices to produce ethanol.
(a) Saccharomyces cerevisiae
(b) Clostridium butylicum
(c) Trichodermapolysporum
(d) Penciliumnotatum
Answer:
(a) Saccharomyces cerevisiae

Question 10.
Over use of chemical fertilizers harmfully affect the environment and human survival. Make discussion . points to reduce the use of chemical fertilizers.
Answer:
Organic farming and use of biofertilizers.

Question 11.
Biogas is a terminology that we hear in our day to day life. Name the gases produced in biogas plant.
Answer:
Methane, CO₂, H₂

Plus Two Zoology Microbes in Human Welfare Two Mark Questions and Answers

Question 1.
Find out the name of the microbes from which Cyclosporin A (An Immunosuppressive drug) and statins (Blood cholesterol-lowering agent) are obtained.
Answer:

• Cyclosporin A-Trichoderma polysporum
• Statins – Monascus purpureus

Question 2.
The dough which is used for making foods such as dosa and idli give a puffed-up appearance.

1. What is the prodess involved here?
2. Name the gas produced?

Answer:

1. Fermentation
2. CO₂

Question 3.
Microbes synthesis a number of industrial product like beverages and antibiotics.

1. Name the microbes involved in the production of beverages.
2. Classify the types of alcoholic drinks based on raw material and processing.

Answer:

1. Saccharomyces cerevisiae (Brewer’s yeast)
2. Alcoholic drinks without distillation – Wine and Beer Alcoholicdrinkswith distillation-Whisky, brandy, rum.

Question 4.
Identify the microorganism.

1. Symbiotic association with roots of leguminous plant.
2. Microbe responsible for the preparation of dough.
3. Bacteria used in the production of biogas.
4. Microbes responsible for the conversion of milk to curd.

Answer:

1. Rhizobium
2. Saccharomyces cerevisiae
3. Methanobacterium
4. Lactobacillus

Question 5.
Your family has decided to minimize the use of LPG (Liquid petroleum gas). List out the steps that you would adopt to install a biogas plant at your house premises.
Answer:

1. A concrete tank in which bio-wastes are collected and a slurry of dung is fed.
2. A floating cover over the slurry.
3. An outlet connected to pipe to supply biogas.
4. Another outlet to remove spent slurry to be used as fertiliser.

Question 6.
BOD testing is widely used in detecting the polluting potential of different water sources. How BOD helps in analysing the polluting potential? BOD is the measure of organic matter in the water. The greater the BOD of wastewater more is its polluting potential.
Answer:
Auto immune response
Eg: Rhuematoid arthritis, Myasthenia gravis.

Question 7.
Microbes play an important role in production of biogas.

1. Name the group of bacteria, which produce biogas. Give an example.
2. Which are the common habitat of these bacteria.

Answer:

1. The bacteria are collectively called methanogens. Eg: Methanobacterium
2. Methanogens are commonly found in, Anaerobic sludge Rumen of cattle, Cattle dung, etc.

Question 8.
In sewage treatment floes play a major role.

1. What are floes?
2. State their role in effluent treatment and their ultimate fate in sewage treatment tank.

Answer:

1. Floes are masses of bacteria associated with fungal filaments to form mesh-like structures.
2. Floes consume the organic matter in the effluent and reduces the BOD. Then the effluent passed into settling tank, where floes are allowed to sediment forming activated sludge.

Question 9.
In which food would you find lactic acid bacteria? Mention some of their useful applications.
Answer:
In curd Other Applications are,

1. Increases nutritional quality
2. Checking disease-causing microbes

Question 10.
Microbes can be used to decrease the use of chemical fertilizers and pesticides? Explain how this is accomplished.
Answer:
By switch to organic farming using biofertilizers like bacteria, fungi, and cyanobacteria.
Eg: Rhizobium, Glomus, Anabaena, Nostoc etc.

Question 11.
A person has suffered a heart attack due to a floating clot in his coronary artery.

1. Name the bacterium that can save him.
2. Mention its product and its action.

Answer:

1. Strep to cocus
2. Strep to kinase. It is a clot-buster

Question 12.
“Biogas become popular on now a days as a source of energy.” Mention the merits of Biogas.
Answer:

• Clean & Ecofriendly fuel
• Produce fewer pollutants
• Can be easily stored and transported
• Recycling ensures
• Renewable energy.

Question 13.
Microbes play a dual role when used for sewage treatment as they not only help to retrieve usable water but also generate fuel. Write the points how this happens.
Answer:
Heterotrophic microbes naturally present in sewage are used. Vigorous growth of aerobic microbes as floes use up organic matter in effluent and reduce BOD of waste water.

Other kinds of bacteria grow in it anaerobically and digest the bacteria and fungi called floes. As they digest floes, as mixture of CH₄, H₂S and CO₂ (biogas) are evolved, which can be used as a fuel.

Question 14.
Common yeast is known as Baker’s yeast and also as Brewer’s yeast. Justify.
Answer:
Common yeast is employed in the fermentation of

1. Dough, used for making bread, cakes in bakeries.
2. Fruit juices and malt in breweries for the production of alcoholic beverages: hence it is known as both as baker’s and brewer’s yeast.

Question 15.
What is the difference in production of wine and whisky?
Answer:
Wine is produced without distillation while whisky is produced by distillation.

Question 16.
Match column A with column B and column C

Answer:

Question 17.
Milk is converted to curd by the action of micro organisms

1. Name the microorganism that convert milk to curd.
2. Explain the superior nutritional quality of curd over milk.

Answer:

1. LAB (Lactic Acid Bacteria)
2. Increasing Vit. B₁₂, Check disease-causing microbes in stomach.

Question 18.
Ramu likes fresh juices than bottled juices

1. As a plus two biology student, give your opinion about his habit.
2. Why bottled juices are clearer than fresh juices? Critically evaluate its harmful effects.

Answer:

1. bottled juice is not good for health,
2. Use of Pectinase and Protease make clear solutions. It contains large number of preservatives and other chemicals.

Question 19.
Swiss cheese contains large holes

1. Describe the formation of large holes in cheese
2. Name the end product of the process mentioned

Answer:

1. Production of large amount of CO₂ by a bacterium called Propionibacterium sharmanii during fermentation
2. CO₂

Question 20.
Farmers cultivate pea plant as an intermediate crop in the paddy fields. After harvesting they remove all parts of the pea plant from their crop land

1. Do you think the action of removing all parts of the pea plant from the field is a good agricultural practice.
2. Justify your answer.

Answer:

1. No,
2. The root nodules of leguminous plants(Pea plant) have symbiotic association of Rhizobium. These bacteria fix atmospheric nitrogen which is used by the plant as nutrient.

Question 21.
Many pathogenic microbes and large amounts of organic matter are found in sewage.

1. During sewage treatment primary sludge is produced. Define Primary sludge.
2. Compare it with activated sludge.

Answer:

1. All solids that settle during primary treatment are called primary sludge.
2. During secondary treatment the effluent is passed into a settling tank where the bacterial ‘floes’ are allowed to sediment. This sediment is called activated sludge.

Question 22.
The untreated sewage when discharged directly into rivers cause aquatic pollution and spread various diseases. Suggest suitable remedies to overcome the problem. Give emphasis on Ganga action plan and Yamuna action plan.
Answer:
The aim of Ganga Action Plan and Yamuna Action Plan is to save major rivers of our country from pollution. These plan is proposed to set up of sewage treatment plants and discharge less polluted water into the rivers.

This helped to avoid many water-borne diseases and through which major rivers can be conserved.

Question 23.
“BOD is commonly calculated as an index of water pollution”.

1. Do you agree with the statement? Why?
2. Expand BOD.

Answer:

1. Yes, BOD test measures the rate of uptake of oxygen by micro organisms in a sample of water, indirectly. BOD is the measure of the organic matter present in water.
2. biochemical oxygen demand.

Question 24.
Expand the terms given below.

• KVIC
• IARI

Answer:

• KVIC: Khadi and Village Industries Commission
• IARI: Indian Agricultural Research Institute.

Question 25.
Today we cannot imagine a world without antibiotics.

1. Define antibiotics?
2. Name the first antibiotic to be discovered.

Answer:

1. Antibiotics are chemical substances, which are produced by some microbes and can kill or retard the growth of other disease-causing microbes.
2. Penicillin

Question 26.
Complete the table.

Answer:

Microbes	Acids/Uses
Aceto bacter aceti	Acetic acid
Methano bacterium	Biogas
Lactobacillus	Lactic acid
Penicillium notatum	Penicillin

Question 27.
Your local self-government is newly introducing a project on waste management and installing Biogas plants at all homes. As a plus two biology student, briefly explain the working of biogas plant.
Answer:
The biogas plant consists of a concrete tank (10-15 feet deep) in which bio-wastes are collected and a slurry of dung is fed.

The biogas plant has an outlet, which is connected to a pipe to supply biogas to nearby houses. The spent slurry is removed through another outlet and used as fertiliser. The biogas thus produced is used for cooking and lighting.

Question 28.
Farmers cultivate pea plant as an intermediate crop in the paddy fields. After harvesting they remove all parts of the pea plant from their crop land

1. Do you think the action of removing all parts of the pea plant from the field is a good agricultural practice.
2. Justify your answer.

Answer:

1. No,
2. The root nodules of leguminous plants(Pea plant) have symbiotic association of Rhizobium. These bacteria fix atmospheric nitrogen which is used by the plant as nutrient.

Question 29.
Many pathogenic microbes and large amounts of organic matter are found in sewage.

1. During sewage treatment primary sludge is produced. Define Primary sludge.
2. Compare it with activated sludge.

Answer:

1. All solids that settle during primary treatment are called primary sludge.
2. During secondary treatment the effluent is passed into a settling tank where the bacterial ‘floes’ are allowed to sediment. This sediment is called activated sludge.

Question 30.
The untreated sewage when discharged directly into rivers cause aquatic pollution and spread various diseases. Suggest suitable remedies to overcome the problem. Give emphasis on Ganga action plan and Yamuna action plan.
Answer:
The aim of Ganga Action Plan and Yamuna Action Plan is to save major rivers of our country from pollution. These plan is proposed to set up of sewage treatment plants and discharge less polluted water into the rivers.

This helped to avoid many water – borne diseases and through which major rivers can be conserved.

Question 31.
Three water samples namely river water, untreated sewage water, and secondary effluent discharged from a sewage treatment plant were subjected to BOD test. The samples were labelled A, B, and C, but the Laboratory attendant did not note which was which. The BOD values of the three samples A, B, and C were recorded as 20mg/L, 8 mg/L, and 400 mg/L, respectively. Which sample of the water is most polluted? Why?
Answer:
The sample C is more polluted. So the bottle labelled C was untreated sewage water, because it has the highest BOD 400mg/L.

BOD is a measure of organic matter present in water. The greater the BOD of waste water, more is its
polluting potential.

Plus Two Zoology Microbes in Human Welfare Three Mark Questions and Answers

Question 1.
Match column A with column B and column C

Answer:

Question 2.
Name the household products, the following microbes help to produce.

1. LAB
2. Saccharomyces cerevisae
3. Propionibacteriumsharmanii

Answer:

1. LAB – Curd
2. Saccharonyces cerevisiae (Baker’s yeast) – Bread
3. Propionibacterium Sharmanii – Swiss cheese

Question 3.
One of the most significant discoveries of the twentieth century was the production of antibiotics from microbes.

1. How will you define antibiotic?
2. Name the first antibiotic and who discovered it?
3. Name some deadly diseases which can be treated by antibiotics.

Answer:

1. Antibiotics is a chemical substance produced by some microbes and can kill or retard the growth of other disease-causing microbes.
2. Alexander Fleming discovered the first antibiotic Penicillin, while working on Staphylococcus bacteria.
3. Plague, Whooping cough, Diphtheria, Leprosy, etc.

Question 4.
Match the following.

Microbe	Use
a. Penicillium notatum	Biogas
b. Methano bacterium	Penicillin
c. Monascus purpureus	Biofertilizer
d. Nostoc	Cholesterol-lowering
e. Bacillus thuringiensis	Immune suppressive agent
f. Trichoderma polysporum	Biological control

Answer:

Microbe	Use
a. Penicillium  notatum	Penicillin
b. Methano bacterium	Biogas
c. Monascus purpureus	Cholesterol lowering
d. Nostoc	Biofertilizer
e. Bacillus thuringiensis	Biological control
f. Trichoderma polysporum	Immune suppressive agent

Question 5.
Many microbes are used for the commercial production of chemicals, acids, enzymes, etc.
1. Give examples for acid-producing microbes and the acids.
2. Name the enzymes produced by microbes and their use.
3. What are

• Cyclosporin A
• Statins

Answer:
1.

• Aspergillusniger(fungus)-Citric acid
• Acetobacter aceti (Bacterium) – Acetic acid
• Clostridium butylicum (Bacterium) – Butyric acid
• Lactobacillus (Bacterium) – Lactic acid

2.

• Lipases – In detergents for removing oily stains from the laundry.
• Pectinases (and Proteases) – clearing bottled juices.
• Streptokinase – As ‘clot buster’ for removing clots from blood vessels of heart patients

3.

• Cyclosporin A is a bioactive molecule used as an immuno suppressive agent in organ transplant patients. It is produced by a fungus Trichoderma polysporum.
• Statins are blood-cholesterol lowering agents produced by the yeast Monascus purpureus.

Question 6.
Microbes play a major role in the treatment of sewage, which is a main cause of pollution. Some terms related to sewage treatment are given. What are they?

1. Sewage
2. B.O.D.
3. Floes

Answer:
1. Sewage is the muncipal waster water generated in cities and towns everyday, which contains large amount of organic matter and pathogenic microbes.

2. Biological Oxygen Demand (B.O.D) refers to the amount of 02 that would be consumed, if all the organic matter in one litre of water were oxidized by bacteria.

3. Floes are masses of bacteria associated with fun-gal filaments to form mesh like structures.

Question 7.
Microbes are widely applied as biocontrol agents in biological farming approach.

1. What is Biocontrol?
2. What is the advantage of this over conventional chemical methods?
3. Give two examples for biocontrol.

Answer:
1. Biocontrol refers to the use of biological methods for controlling plant diseases and pests.

2. Chemicals like insecticides and pesticides are toxic and extremely harmful to human beings and animals. They also pollute the environment. Use of biocontrol measures reduce the dependence on toxic chemicals.

3.

• Bacillus thuringiensis (Bt)
• Trichoderma

Question 8.
A part of the flow chart showing sewage treatment is given below. Complete it with other steps involved in sewage treatment.

Answer:

Plus Two Zoology Microbes in Human Welfare NCERT Questions and Answers

Question 1.
What is the key difference between primary and secondary sewage treatment?
Answer:
Primary treatment involves the removal of large sized floating and suspended solids by physical methods, while secondary treatment involves decomposition of organic matter by microbial action.

Question 2.
Do you think microbes can also be used as source of energy? If yes, How?
Answer:
Yes.
The microbes present in activated sludge are digested an aerobically to generate an inflammable biogas or gobar gas which is used as source of energy.

Question 3.
Microbes can be used to decrease the use of chemical fertilizers and pesticides. Explain how this can be accomplished?
Answer:
By the use of biofertilizers and biological pest control method. The use of chemical fertilizers and pesticides can be reduced.

The fertility of the soil depends not only on its chemical composition but also on the presence of useful microbes in it, which enrich the nutrient quality of the soil. The main source of biofertilizers are bacteria, fungi and cyanobacteria.

Question 4.
Three water samples namely river water, untreated sewage water, and secondary effluent discharged from a sewage treatment plant were subjected to BOD test. The samples were labeled A. B. and C, but the laboratory attendant did not which was which. The BOD values of the three samples A, B, and c were recorded as 20 mg/L. 8 mg/L and 400 mg/L respectively. Which sample of the water is most polluted? Can you assign the correct label to each assuming the river water is relatively clean?
Answer:

1. Sample A-Secondary effluent
2. Sample B – River Water
3. Sample C – Untreated Sewage water.

Question 5.
Find out the name of the microbes from which cyclosporine A and Statins are obtained.
Answer:

1. Cyclosporin A-Trichoderma Polysporum (a fungus)
2. Statins – Monascus Purpureus (a yeast)

Question 6.
Find out the role of microbes in the following and discuss it with your teacher –

1. Single-cell protein (SCP)
2. Soil.

Answer:
1. SCP:-
It is protein-rich microbial biomass which can be used as food and feed. It has low-fat content. The common SCP are Spirulina. Yeast and Fusarium graminearum.

2. Soil:-
Microbes play an important role in decomposition of organic matter and thus cause mineralization of the soil. The are used as biofertilizers and biopesticides.

Question 7.
Arrange the following in the decreasing order (most important first) of their importance, for the welfare of human society. Give reasons for your answer, Biogas, citric acid, Penicillin, and curd.
Answer:
Penicillin, biogas, curd, critic acid. penicillin fan antibiotic is used to cure a number of bacterial diseases.

Question 8.
Bacteria cannot be seen with the naked eyes but can be seen with the help of a microscope. If you have to carry a sample from your home to your biology laboratory to demonstrate the presence of microbes under a microscope, which sample would you carry and why?
Answer:
Bacteria can be grown and multiplied on nutritive culture media in aseptic conditions to form colonies which can be transported from the home to biology laboratory where these can be demonstrated under a microscope. In homes easily available source of microbial culture is curd. It is with Lactic acid bacteria.

Question 9.
Give examples to prove that microbes release gases during metabolism.
Answer:
1. Puffing up of dough, during making of dosa, idli or bread, is due to production of CO₂ gas during the fermentation process.

2. Appearance of large holes in “swiss cheese” is due to C0₂ produced during fermentation by the bacterium Propionibacterium sharmanii.

3. During secondary treatment of sewage in sewage treatment plants, a number of gases like methane, H₂S and CO₂ are produced during microbial digestion of organic compounds.

4. Methanogens(e.g. Methano bacterium) present in the rumen (a part of stomach) of cattle are being used in biogas plants to produce biogas as energy source.

Question 10.
In which food would you find lactic acid bacteria? Mention some of their useful applications.
Answer:
1. Lactic acid bacteria (LAB) are commonly found in milk and under suitable condition, these multiply and produce acids which coagulate and partially digest the milk proteins and change the milk into curd.

2. LAB are also found in the human stomach where these prevent the growth of certain disease-causing microbes.

Question 11.
In which way microbes have played a major role in controlling diseases caused by harmful bacteria?
Answer:
Antibiotics are the chemical substances which are derived from certain useful microbes and are employed to kill or retard the growth of disease-causing microbes.

So antibiotics are being used in controlling a number of bacterial diseases like cholera, pneumonia, typhoid, syphilis, whooping cough, diphtheria, etc.

Question 12.
Name any two species of fungus, which are used in the production of the antibiotics.
Answer:

Question 13.
Name some traditional Indian foods made of wheat, rice and Bengal gram (or their products) which involve using microbes.
Answer:

Plus Two Zoology Microbes in Human Welfare Multiple Choice Questions and Answers

Question 1.
Which of the following was used as a bioweapon agent in America?
(a) Botulinuni
(b) Anthrax (Bacillus anathracis)
(c) Polio vims
(d) AIDS virus
Answer:
(b) Anthrax (Bacillus anathracis)

Question 2.
During an aerobic digestion of organic waste, such as in producing biogas, which one of the following is left undegraded?
(a) Hernicellulose
(b) Cellulose
(c) Lipids
(d) Lignin
Answer:
(d) Lignin

Question 3.
Azolla is used as a biofertilizer because it
(a) multiplies very fast to produce massive bio
(b) has association of nitrogen-fixing Rhizobium
(c) has association of nitrogen-fixing cyanobacteria
(d) has association of Mycorrhiza
Answer:
(c) has association of nitrogen-fixing cyanobacteria

Question 4.
Which is a bioinsecticide?
(a) cactoblastis cactorum
(b) Anabaena
(c) Bacillus thuringiensis
(d) Rhizobium
Answer:
(c) Bacillus thuringiensis

Question 5.
One of the major difficulties in the biological control of insect pest is that
(a) the method is less effective as compared with the us of insecticides
(b) the predator does not always survive when transferred to a new environment
(c) the predator develops a preference to other diets may itself become a pest
(d) the practical difficulty of introducing the predat specific area
Answer:
(b) the predator does not always survive when transferred to a new environment

Question 6.
Biogas is pathogen-free because
(a) anaerobic digestion removes pathogens and bacteria
(b) it is toxic to pathogens
(c) during decomposition, it produces antibiotics
(d) cattle dung is pathogen-free
Answer:
(c) during decomposition, it produces antibiotics

Question 7.
Green manures are prepared from
(a) Saccharum officinarum
(b) Zea mays
(c) Crotalariajuncea
(d) Sorghum Vulgare.
Answer:
(c) Crotalariajuncea

Question 8.
Insecticide obtained from neem plant is
(a) pyrethrin
(b) pyrethroid
(c) thiocarbamate
(d) azadirachtin
Answer:
(d) azadirachtin

Question 9.
Biogas production from waste biomass with the help of methanogenic bacteria is
(a) multi-step process
(b) one-step process
(c) two-step process.
(d) three-step process
Answer:
(a) multi-step process

Question 10.
From which one of the following plants, the insecticide pyrethrum is prepared?
(a) Vetivera
(b) Cymbopogon
(c) Chrysanthemum
(d) 7ephrosia
Answer:
(c) Chrysanthemum

Question 11.
lPM (Integrated Pest Management) involves
(a) tissue culture
(b) biological control
(c) biofertilizers
(d) confusion technique
Answer:
(b) biological control

Question 12.
The lactic acid bacteria is involved in
(a) conversion of milk into curd
(b) conversion of curd into ghee
(c) lactic acid fermentation
(d) both a and c
Answer:
(d) both a and c

Question 13.
In the case of the ‘Swiss cheese’ with large hole is due to the production of
(a) CO
(b) CO₂
(c) CH₄
(d) C₂H₅OH
Answer:
(b) CO₂

Question 14.
Roquefort cheese is made by
(a) bacteria
(b) fungi
(c) nematode
(d) mycoplasma
Answer:
(b) fungi

Question 15.
The important distillation products are
(a) whisky
(b) brandy
(c) rum
(d) all the above
Answer:
(d) all the above

Question 16.
Alexander Fleming observed that the chemical produced by mould in one of his unwashed culture plates restricted the growth of
(a) streptococcus
(b) staphylococcus
(c) pneumococcus
(d) bacillus
Answer:
(b) staphylococcus

Question 17.
The microbe that produce butyric acid belongs to
(a) virus
(b) mycoplasma
(c) bacteria
(d) fungi
Answer:
(c) bacteria

Question 18.
The ‘clot buster’ for removing clots from the blood vessels of patients is mainly obtained from
(a) streptococcus
(b) staphylococcus
(c) pneumococcus
(d) bacillus
Answer:
(a) streptococcus

Question 19.
Trichoderma polysporum is helpful to the patients subjected to organ-transplant because it produce immunosuppressive agent called as
(a) interferon
(b) cyclosporine A
(c) Streptokinase
(d) statins
Answer:
(b) cyclosporine A

Question 20.
Which one of the following microbe produce Statins
(a) Bacillus thuringiensis
(b) Saccharomy cescerevisiae
(c) Trichoderma polysporum
(d) Monascus purpureus
Answer:
(d) Monascus purpureus

Question 21.
The major part of activated sludge is subjected to
(a) aerobic digestion
(b) anaerobic digestion
(c) both a and b
(d) none of the above
Answer:
(b) anaerobic digestion

Plus Two Zoology Microbes in Human Welfare SCERT Sample Questions and Answers

Question 1.

1. Name the microorganism which produced butyric acid. (1)
2. ‘Secondary treatment is sewage water treatment is called biological’. Justify. (1)

Answer:

1. Clostridum butylicum
2. The primary effluent is passed into large aeration tanks, is carried with the help of aerobic bacteria.