The comprehensive approach in SCERT Class 8 Basic Science Textbook Solutions Chapter 16 Tree of Life Important Questions ensure conceptual clarity.
Tree of Life Extra Questions and Answers Class 8 Basic Science Chapter 16 Kerala Syllabus
Tree of Life Class 8 Important Questions
Question 1.
Characteristics of Kingdom Fungi are given below. Choose the correct option.
i. They are Prokaryotes.
ii. They have a cell wall made of chitin.
iii. They are autotrophs containing chlorophyll.
iv. They are saprophytes.
(a) i, iii correct
(b) ii, iv correct
(c) i, ii, iv correct
(d) All are correct
Answer:
(b) ii, iv correct
Question 2.
Rules of Binomial Nomenclature developed by Carl Linnaeus are given. Choose the correct statements.
i. The scientific name has two parts: species name first, genus name second.
ii. The first letter of the Genus name should be capital.
iii. The first letter of the Species name should be capital.
iv. The scientific name should be printed in italics or underlined if handwritten.
(a) i, ii, iii correct
(b) ii, iv correct
(c) i, iv correct
(d) All are correct
Answer:
(b) ii, iv correct
Question 3.
Which of the following statements correctly define a ‘Species’ according to the biological concept?
i. It is the most basic level of classification.
ii. Organisms within a species look exactly identical.
iii. Members of a species can naturally reproduce to form fertile offspring.
iv. It is the level just below Kingdom in classification.
(a) i, iii correct
(b) i, ii, iii correct
(c) iii, iv correct
(d) i only correct
Answer:
(a) i, iii correct
Question 4.
Complete the missing levels in the hierarchical classification system shown below.
Kingdom → Phylum → (a) _______ → Order → (b) ________ → Genus → (c) ________
Answer:
a) Class b) Family c) Species
Question 5.
Complete the following table summarizing characteristics of the Five Kingdoms.
| Kingdom | Nuclear Type (Prokaryotic/Eukaryotic) | Mode of Nutrition (Autotroph/Heterotroph/ Saprotroph | Example |
| Monera | (a) …………………. | Autotroph or Heterotroph | Bacteria |
| Fungi | Eukaryotic | (b) …………………. | Yeast |
| Plantae | Eukaryotic | (c) …………………. | Coconut Tree |
Answer:
| Kingdom | Nuclear Type (Prokaryotic/Eukaryotic) | Mode of Nutrition (Autotroph/Heterotroph/ Saprotroph | Example |
| Monera | (a) Prokaryotic | Autotroph or Heterotroph | Bacteria |
| Fungi | Eukaryotic | (b) Saprotroph | Yeast |
| Plantae | Eukaryotic | (c) Autotroph | Coconut Tree |
Question 6.
Fill in the missing classification levels for the Tiger (Panthera tigris).
| Level | Taxon |
| Kingdom | Animalia |
| Phylum | Chordata |
| Class | (a) ……………………. |
| Order | Carnivora |
| Family | (b) ……………………. |
| Genus | Panthera |
| Species | (c) ……………………. |
Answer:
a) Mammalia,
b) Felidae,
(c) tigris
Question 7.
Who introduced the Five-Kingdom classification system, and what were the five kingdoms proposed?
Answer:
Robert H. Whittaker introduced the Five-Kingdom classification. The five kingdoms are Monera, Protista, Fungi, Plantae, and Animalia.
Question 8.
What is Taxonomy?
Answer:
Taxonomy is the branch of science that deals with classifying organisms by comparing their characteristics, identifying similarities and differences, and giving them scientific names.
Question 9.
What contribution did John Ray make to the field of classification?
Answer:
John Ray initiated the scientific method of classification and was the first to use the term ‘species’.
Question 10.
Explain the need for a universally accepted scientific naming system like Binomial Nomenclature.
Answer:
The same organism often has different common names in different regions or languages (e.g., Papaya). This creates confusion and makes it difficult to accurately identify and study organisms globally. Binomial Nomenclature provides a unique, two-part scientific name (Genus and species) that is universally accepted, overcoming language barriers and ensuring clarity in scientific communication.
Question 11.
Why was Kingdom Monera split into two separate kingdoms (Archaebacteria and Eubacteria) in the Six-Kingdom classification?
Answer:
The split was proposed by Carl Woese based on modern scientific observations, particularly differences at the molecular level (like genetics and cell wall composition) which indicated that the organisms originally grouped in Monera actually represented two very distinct and ancient lineages of prokaryotes.
Question 12.
Explain the main limitation of classifying organisms based only on their external structure, as was done in early classification systems.
Answer:
Classifying based only on external structure can be misleading because organisms that look similar externally may not be closely related evolutionarily or genetically (like Wolffia and Salvinia). Conversely, organisms that look
different might be closely related. Modern classification uses evolutionary and genetic data along with morphology for a more accurate system.
Question 13.
Identify the organism that belongs to Kingdom Monera from the following list: Amoeba, Yeast, Paramecium, Bacteria.
Answer:
Bacteria. (Amoeba and Paramecium are Protista; Yeast is Fungi).
Question 14.
Find the odd one out based on the Five-Kingdom classification: Mushroom, Mould, Yeast, Euglena.
Answer:
Euglena.
Reason: Mushroom, Mould, and Yeast belong to Kingdom Fungi. Euglena belongs to Kingdom Protista.
Question 15.
Which of the following is NOT an example of a species? Human beings, Cats, Mammalia, Coconut Tree.
Answer:
Mammalia.
Reason: Human beings (Homo sapiens), Cats (Felis catus), and Coconut Tree (Cocos nucifera) represent specific species. Mammalia is a Class, a higher level of classification that includes many different species.
Question 16.
Analyse the statement and answer the questions.
The scientific name of dog is Canis familiaris
a. How is this method of giving scientific names to organisms known as?
b. What does the words Canis and familiaris in the scientific name indicate?
Answer:
a. Binomial nomenclature
b. Canis indicates the name of the genus and the ‘familiaris’ indicates the name of the species.
Question 17.
Cocos nucifera is the scientific name of coconut. Identify the level of classification indicated by the underlined part.
Answer:
Genus
Question 18.
The various levels of classification of human beings based on the six kingdom classification are given below. Complete the table suitably.
| Domain | Eukarya |
| Kingdom | a. ________ |
| Phylum | Chordata |
| Class | b. ________ |
| Order | Primates |
| Family | Hominidae |
| Genus | c. ________ |
| Species | d. ________ |
Answer:
a. Animalia
b. Mammalia
c. Homo
d. Sapiens
Question 19.
Find the correct pair from the following.
i. Robert Hooke-Discovered the centre of the cell
ii. Robert H Whittaker – 5 Kingdom classification
iii. M. J. Schleiden – Found animal body is made up of cells
Answer:
ii. Robert. H. Whittaker – 5 kingdom classification
Question 20.
Analyse the statement and answer the following questions.
According to the Binomial nomenclature, scientific name of human being is Homo sapiens.
a) What does the First word Homo indicate
b) Who proposed the Binomial nomenclature?
c) What is the merit of Binomial nomenclature?
Answer:
a) Genus
b) Carl Linnaeus
c) Each organism is known by different names in different places and in different languages. So a commonly acepted name is needed for identifying organisms.
Question 21.
Identify the relation between the words of first pair and complete the second pair suitably
a) Mushroom: Fungi
Amoeba: …………………….
b) Cat: Felis domesticus
Crow: ……………………
Answer:
a. Protista
b. Corvus splendens
Question 22.
Rewrite the following sentences correctly. If there is any error in the underlined part
a. Aristotle is known as the father of Botany
b. Monera includes unicellular organisms with distinct nucleus
c. Five Kingdom classification was introduced by Robert H Whitaker
Answer:
a. Theophrastus is known as the father of Botany
b. Protista includes unicellular organisms with distinct nucleus
Question 23.
Name of two scientists related to taxonomy is given below. Write their contributions in this field.
i) Charakan
ii) John Ray
Answer:
a. Charakan Wrote the treatise ‘Charakasamhita1 including around 200 plants and animals.
b. John Ray Recorded more than 18000 plants in his book named Historia generalis plantarum’ Used the term ‘species’ for the first time.
Question 24.
The scientific name of Tiger is Panthera Tigris.
a. What do the words ’Panthera’ and ’Tigris’ indicate ?
b. What are the advantages of giving scientific name to organisms?
c. Name the scientist who proposed the scientific naming of organisms?
Answer:
a. Panthera indicates Genus and Tigris indicates Species
b. By giving scientific name, organisms can be easily identified all over the world and it helps to solve the difficulties arising out of an organisms known by various names in different languages and regions.
c. Carl Linnaeus
Question 25.
Write the taxonomic hierarchy of coconut tree by choosing appropriate terms from the box
Plantae cocos Series
Nucifera Dicotyledonae
Genus Monocotyledonae
| Domain | Eukarya |
| Kingdom | i. …………………….. |
| Phylum | Angiospermophyta |
| Class | ii. …………………… |
| iii. …………………… | Calysinae |
| Family | Aracasiae |
| iv. ……………………… | v. …………………… |
| Species | vi. …………………. |
Answer:
i. Plantae
ii. Monocotyledonae
iii. Order
iv. Genus
v. Cocos
vi. Nucifera
Question 26.
Correct the mistakes if any in the underlined part.
a. Taxonomic keys are the scientific indicators used for identifying and classifying plants and animals.
b. Genus is the basic level of classification.
c. The first word of the scientific name indicates the genus and the second word indicates the species.
Answer:
Species is the basic level of classification
Question 27.
Name of scientists who contributed in the field of taxonomy are given below. Identify their contribution which is given in the box and make pairs.
A) Carl Woese
B) John Ray
C) Theophrastus
d) R.H. Whittaker
i. Classified the organisms as those with red blood cells and those without red blood cells.
ii. Classified plants into annuals, biennials and perennials.
iii. Six kingdom classification.
iv. Five kingdom classification.
v. Used the term species for the first time
Answer:
i. Aristotle
ii. Theophrastus
iii. Cari woese
iv. Robert H Whittaker
v). John ray
Question 28.
Identify the word pair relation and fill the blanks.
a. 2 Kingdom classification:
Carls Linnaeus :: 5 kingdom
Classification: ………………………….
b. Mushrooms: Fungi::
Bacteria: ………………………….
c. Aristotle – Father of Biology
Carls Linnaeus – ………………………….
d. Golden shower : Cassia fistula
:: ………………………….: Corvus splendens
e. Charaka: Father of Ayurveda
:: ………………………….: Father of Botany
Answer:
a. R H Whittaker
b. Monera
c. Father of Taxonomy
d. Crow
e. Theophrastus
Question 29.
Identify the odd one and write the characteristic features of others.
a. Lion, Tiger, Rabbit, Cat.
b. Genus, Order, Carl Linnaeus, Phylum.
Answer:
a. Rabbit – Others including order Carnivora
b. Carl Linnaeus – He is the Father of Modern Taxonomy. Others are different levels of classification.
Question 30.
Which organism is most suitable for the following indicators (amoeba, bacteria, virus, Fungus)
• Lives only in living cell
• Pathogen
• Only genetic material and a protein covering.
Answer:
Virus
Question 31.
Find out the scientists suitable to the statements given.
i. Author of Charaka Samhitha
ii. Author of Historia Generalis Plantarum
iii. Father of Modern Taxonomy
iv. Father of Biology
Answer:
i. Charaka
ii. John ray
iii. Carl Linnaeus
iv. Aristotle
Question 32.
Complete the table
Organism Scientific Name
Elephant ……………………..
Peacock ……………………..
Dog ……………………..
Hibiscus ……………………..
Neem ……………………..
Paddy
……………………..
Answer:
Elephas Maximus / Elephas Indicus
• Pavo Cristatus
• Canis Familiaris
• Hibiscus Rosasinensis
• Azadirachta Indica
• Oryza sativa
Question 33.
What are limitations in the system of classification of Carl Linnaeus.
Answer:
Some lower organisms share the characters of both animals and plants. So it is difficult to recognize them as plants or animals. Linnaeus considered only plants and animals for his classification. Microscopic organisms like bacteria, fungus, protozoa etc were not included either in plant kingdom or in animal kingdom. Certain animals which were included in the classification of Linnaeus shows characters of both the animal and plant kingdoms. Eg: Euglena protozoan shows locomotory movements like animals, but it contains chlorophyll like plants.
Question 34.
Hints about some organisms are given below. Name the kingdom to which these organisms belong.
a. Multicelluar heterotropic organisms with a nucleus and capacity for locomotion.
b. Multicelluar heterotropic, nonmotile organisms with a nucleus.
c. Unicelluar organisms with a nucelus.
d. Multicelluar, autotropic, nonmotile organisms with a nucleus.
Answer:
a. Animalia
b. Fungi
c. Protista
d. Plantae
Question 35.
Write the scientific name of following animals and plants.
Coconut, paddy, wheat, crow, mango, grapes
Answer:
Coconut – Cocos nucifera
Paddy – Oryza sativa
Wheat – Triticum aestivum
Crow – Corvus splendens
Mango – Mangifera indica
Grapes – Vitis vinifera
Question 36.
What are two important characters of species?
Answer:
- Species is a group of organisms that can freely interbreed to produce fertile offsprings.
- A group of organisms that closely resemble each other in structure biochemical make up and external charecteristics but which are genetically different. In one species there may be sub species.
Question 37.
“The method of classification adopted by Whittakar is much better than the method adopted by Carl Linnaeus the father of the science of classification. What is your response to this statement?
Answer:
The classification of Linnaeus had only two kingdom, plants and animals. He did not consider bacteria, protozoa, fungus etc. Certain characters of animals considered by Linnaeus for classification are found in both the kingdoms, eg. photosynthesis found in plants is seen in some animals like Euglena.
Certain characters of animals can be seen in plants also, eg certain types of algea. But Whittakar adopted the method of having five kingdoms including protozoa and bacteria.
- Monera,
- protista
- fungi
- plantae
- animalia
Question 38.
Bacteria does not have a well defined Nucleus. Viruses are also like Bacteria. Why is it not possible to include viruses under Monera.
Answer:
Viruses exhibit living nature only when they enter the host cells. On other occasions they do not exhibit living nature. But organisms in Monera are not like that.
Question 39.
How do the levels of classification of plants made by Carl Linnaeus differ from the levels of classification of Animals?
Answer:
Not much differences are there. In the place of ‘Order’ in animal classification, plant classification has series. And in the place of ‘Phylum’ in animal classification. plant classification has ‘Division’.
Question 40.
Cell is the smallest unit of life. But there are certain organisms that live without cell too. Analyse these statement.
Answer:
Life is not possible without a cell. Viruses do not have cells. As it is so, it does not have life when it outside a living cell. As it enters a living cell, it will show the features of life forms. It makes use of the components of the host cell and continues to live. Though it does not have a cell, it can continue its life only after entering a host cell and by making use of its components.
Question 41.
Observe the given statement, and write correct answer if you find false statements.
a. Aristotle is the Father of Biology.
b. John Ray is the Father of Botany.
c. Carl Linnaeus used the term ‘species’ for the first time
d. Charakan proposed binomial nomenclature.
Answer:
a. True
b. False, Theophrastus
c. False, John Ray
d. False, Carl Linnaeus.
Question 42.
Read the following statements and choose the correct option:
Statement I: John Ray was the first scientist to use the term ‘species’.
Statement II: Aristotle classified organisms into five kingdoms.
A) Both Statements are true.
B) Statement I is true, but Statement II is false.
C) Statement I is false, but Statement II is true.
D) Both Statements are false.
Answer:
B) Statement I is true, but Statement II is false. : Explanation: John Ray used the term species (True). Aristotle classified animals by red blood, not 5 kingdoms 9. (Whittaker did that).
Question 43.
Read the following statements regarding classification levels:
Statement I: The level just below Kingdom is Phylum.
Statement II: Species is the basic and smallest unit of classification.
A) Both Statements are correct.
B) Only Statement I is correct.
C) Only Statement II is correct.
D) Both Statements are incorrect.
Answer:
A) Both Statements are correct. : Explanation: Phylum is below Kingdom, and Species is the basic unit. Both are correct.
Question 44.
Assertion (A): According to modern classification, Wolffia and Anthurium are included in the same family, Araceae.
Reason (R): Wolffia and Anthurium look exactly the same in their external structure.
A) Both A and R are true, and R is the correct explanation of A.
B) Both A and R are true, but R is NOT the correct explanation of A.
C) A is true, but R is false.
D) A is false, but R is true.
Answer:
C) A is true, but R is false. : Explanation: They are in the same family due to genetic/evolutionary relationships, despite having different external structures.
Question 45.
Assertion (A): Fungi like mushrooms cannot perform photosynthesis.
Reason (R): Fungi cells lack chlorophyll and are saprophytes.
A) Both A and R are true, and R is the correct explanation of A.
B) Both A and R are true, but R is NOT the correct explanation of A.
C) A is true, but R is false.
D) A is false, but R is true.
Answer:
A) Both A and R are true, and R is the correct explanation of A. : Explanation: Fungi are saprophytes because they lack chlorophyll.
Question 46.
Who introduced the method of Binomial Nomenclature?
A) Robert H. Whittaker
B) Carl Woese
C) Carl Linnaeus
D) Ernst Haeckel
Answer:
(C) Carl Linnaeus
Question 47.
Which of the following organisms belongs to Kingdom Monera?
A) Amoeba
B) Bacteria
C) Mushroom
D) Coconut tree
Answer:
(B) Bacteria
Question 48.
Write the scientific names of the following organisms:
a) Human
b) Tiger
Answer:
a) Human: Homo sapiens
b) Tiger: Panthera tigris
Question 49.
List any two rules that must be followed while writing scientific names (Binomial Nomenclature).
Answer:
Rules of Binomial Nomenclature:
1. The first word is the Genus (starts with a Capital letter).
2. The second word is the Species (starts with a small letter).
(Optional: The name should be in italics).
Question 50.
Why was the Two-Kingdom classification system proposed by Carl Linnaeus considered insufficient? Give one reason.
Answer:
It was insufficient because it did not classify organisms like bacteria, fungi, and some unicellular organisms correctly. For example, Fungi are neither plants (no photosynthesis) nor animals, yet they had to be forced into one of the two groups.
Question 51.
Differentiate between Kingdom Monera and Kingdom Protista based on their cell structure (nucleus) and give one example for each.
Answer:
Monera: Prokaryotes (do not have a distinct nucleus). Example: Bacteria. Protista: Eukaryotes (have a distinct nucleus). Example: Amoeba.
Question 52.
Complete the table below regarding the classification of the Tiger:
| Level | Name |
| Kingdom | Animalia |
| Phylum | (a) ………………. |
| Class | Mammalia |
| Order | (b) ………………. |
| Family | Felidae |
| Genus | (c) ………………. |
Answer:
(a) Chordata
(b) Carnivora
(c) Panthera
Question 53.
Explain the Six-Kingdom Classification system. Who proposed it, and how was the Kingdom Monera divided in this system?
Answer:
Proposed by: Carl Woese.
Explanation: He analyzed the Kingdom Monera and found significant differences among its members. He divided Monera into two separate kingdoms: Archaebacteria and Eubacteria. This, along with Protista, Fungi, Plantae, and Animalia, makes up the six kingdoms.