The comprehensive approach in SCERT Class 8 Basic Science Textbook Solutions Chapter 17 The Beauty of Diversity Important Questions ensure conceptual clarity.
The Beauty of Diversity Extra Questions and Answers Class 8 Basic Science Chapter 17 Kerala Syllabus
The Beauty of Diversity Class 8 Important Questions
Question 1.
Regarding the levels of biodiversity, choose the correct statements.
i. Genetic diversity refers to the diversity at the ecosystem level.
ii. Species diversity refers to the variation within a species.
iii. Ecosystem diversity refers to the variety of different habitats in a region.
iv. Different varieties of mangoes in India represent genetic diversity.
(a) i, ii correct
(b) iii, iv correct
(c) i, iii correct
(d) ii, iv correct
Answer:
(b) iii, iv correct
Question 2.
Choose the correct statements about decomposers.
i. Green plants are examples of decomposers.
ii. Decomposers break down complex molecules in dead remains into simpler ones.
iii. Bacteria and Fungi are examples of decomposers.
iv. Decomposers are placed at the top of the food chain.
a) i, iv correct
b) ii, iii correct
c) i, iii correct
d) All are correct
Answer:
(b) ii, iii correct
Question 3.
Select the correct statements regarding ecological interactions.
i. In mutualism, both organisms benefit.
ii. In parasitism, both organisms are harmed.
iii. In commensalism, one benefits, and the other is neither harmed nor benefited.
iv. Predation is beneficial to both the predator and the prey.
a) i, iii correct
b) ii, iv correct
c) i, ii, iii correct
d) All are correct
Answer:
(a) i, iii correct
Question 4.
Complete the food chain by placing the organisms in the correct sequence: Snake, Eagle, Paddy, Rat.
a) _________ → (b) _________ → (c) _________ → (d) _________
Answer:
a) Paddy
b) Rat
c) Snake
d) Eagle
Question 5.
Fill in the blanks representing the trophic levels in the energy pyramid shown in Illustration 17.4.
Trophic level 4: (a) _________Consumers
Trophic level 3: Secondary Consumers
Trophic level 2: (b) _________Consumers
Trophic level 1: (c) _________
Answer:
(a) Tertiary
(b) Primary
(c) Producers
Question 6.
Complete the diagram illustrating the Carbon Cycle by filling in the processes (A), (B), and (C) based on Illustration 17.7.
Atmospheric CO2 → (A) Plants → (B) Animals → (C) Atmospheric CO2
Answer:
A) Photosynthesis
B) Consumption / Eating
C) Respiration
Question 7.
Define the following terms:
a) Habitat
b) Ecosystem
Answer:
a) Habitat: The natural surroundings where each living being lives.
b) Ecosystem: The community of plants, animals, and microorganisms in an area interacting with each other and with abiotic factors.
Question 8.
Give one example for each of the following ecological interactions:
a) Mutualism
b) Parasitism
Answer:
a) Mutualism: Flower and Butterfly (pollination for nectar) OR Lichens (Algae and Fungus).
b) Parasitism: Flea on a Dog OR Lice on humans.
Question 9.
What is the Red Data Book, and which organisation publishes it?
Answer:
The Red Data Book is a document containing information about rare and endangered animals and plants. It is published by the IUCN (International Union for Conservation of Nature).
Question 10.
Observe Figure 17.3 showing different habitats. List two abiotic (non-living) factors essential for the survival of organisms in the Desert habitat shown.
Answer:
Two abiotic factors essential in a desert are:
Sunlight (provides energy, but also contributes to high temperature).
Water (scarce, crucial for survival). (Other possible answers: Air, Soil type/ Sand).
Question 11.
Illustration 17.5 shows a Vanda plant growing on a tree.
a) Identify this type of ecological interaction.
b) Explain how each organism is affected.
Answer:
a) Commensalism.
b) The Vanda (orchid) benefits by getting support and access to sunlight without harming the tree. The Tree is neither benefited nor harmed.
Question 12.
Figure 17.7 shows deforestation. List two negative impacts of deforestation on biodiversity shown or implied in the comparison with Figure 17.6.
Answer:
Two negative impacts are:
Habitat Loss: The removal of trees destroys the homes and living spaces for many animals and plants seen in Fig 17.6.
Loss of Food Sources: Animals that depend on the trees or other forest plants for food lose their sustenance.
(Other possible answers: Soil erosion, disruption of food webs).
Question 13.
Explain why decomposers like bacteria and fungi are essential for the balance of an ecosystem.
Answer:
Decomposers break down dead organisms and waste products. This process is crucial because it returns essential nutrients (like carbon, nitrogen) back into the soil, water, and air, making them available for producers (plants) to use again. Without decomposers, nutrients would remain locked in dead matter, and the ecosystem would eventually run out of usable nutrients.
Question 14.
Why does the amount of energy available decrease at each higher trophic level in a food chain?
Answer:
Energy transfer between trophic levels is inefficient. When one organism consumes another, a large portion of the energy obtained is used by the consumer for its own life processes (like respiration, movement, maintaining body temperature) and is ultimately lost as heat to the environment. Only a small fraction of the energy is stored in the consumer’s body and becomes available to the next trophic level.
Question 15.
Explain the importance of biodiversity in pollination and seed dispersal.
Answer:
Pollination: Many plants rely on animals (like bees, butterflies, birds – part of biodiversity) to transfer pollen, which is necessary for fertilization and fruit/seed production. Without these pollinators, many plant species, including important food crops, could not reproduce.
Seed Dispersal: Animals (like birds, mammals – part of biodiversity) often eat fruits and disperse the seeds in their droppings far from the parent plant. This helps plants colonize new areas, increasing their chances of survival and maintaining genetic diversity across landscapes.
Question 16.
Evaluate the statement: “Protecting only the top predators like tigers is enough for biodiversity conservation.” Is this sufficient? Explain why or why not.
Answer:
No, protecting only top predators is not sufficient. While important, they are just one part of the complex ecosystem. Biodiversity conservation requires protecting all levels of the food web and their habitats. Producers (plants) form the base, herbivores control plant populations, and decomposers recycle nutrients. Protecting the entire ecosystem, including lower trophic levels and habitats, ensures the long-term survival of top predators and maintains overall ecological balance.
Question 17.
Explain the difference between In-situ and Ex-situ conservation methods, giving one example for each.
Answer:
In-situ conservation: Involves protecting species within their natural habitats. Example: National Parks (like Eravikulam) or Wildlife Sanctuaries (like Periyar).
Ex-situ conservation: Involves protecting species outside their natural habitats, often in controlled environments. Example: Zoological gardens (Zoos) or Botanical gardens.
Question 18.
Evaluate the importance of the People’s Biodiversity Register (PBR) in conservation efforts.
Answer:
The PBR is important because it is a local-level documentation of the biodiversity (microorganisms, plants, animals) present in a specific area, prepared with community participation. This detailed, localized information helps:
Understand the unique characteristics and availability of local species.
Identify species that may need conservation focus.
Involve the local community, making conservation efforts more effective and sustainable.
Provide baseline data for monitoring changes in biodiversity over time.
Question 19.
Classify the following as producers and consumers.
Lizard, Planktons, Paddy, Calotes, Carrot, Grasshopper, Tortoise, Algae, Snake
Answer:
| Producers | Consumers |
| Paddy | Lizard |
| Carrot | Calotes |
| Planktons | Grasshopper |
| Algae | Tortoise |
| Snake |
Question 20.
Find out suitable example for the animal relations mentioned.
i. Parasitism ___________
ii. Mutualism ___________
iii. Commensalism ___________
Crops × Weeds
Mango tree × Vanda
Mango tree × Loranthus
Fish × Heron
Hermit crab × sea anemone
Answer:
i. Mango tree and Loranthus
ii. Hermit Crab – Sea anemone
iii. Mango tree and Vanda.
Question 21.
Which are the different types of conservation of biodiversity?
Answer:
These are mainly two types.
- In-situ conservation in which organisms are conserved within their natural environment
- Ex-situ conservation in which animals are protected out their natural environment.
Question 22.
Complete the illustration Suitably
Answer:
a. Environmental/Ecological services
b. Cultural services
c. Food, Medicine
d. Nutrient Cycle, Pollination
Question 23.
Classify the following into Exsitu and In-situ.
(Zoological Gardens, Sacred Groves, Gene banks, Biosphere Reserves, Botanical Gardens, National parks)
Answer:
| In-situ | Ex-situ |
| National parks | Zoological Gardens |
| Sacred Groves | Gene Banks |
| Biosphere Reserves | Botanical Gardens. |
Question 24.
Expand the following terms.
Answer:
JNTBGRI – Jawaharlal Nehru Tropical Botanic Garden and Research Institute.
MBG – Malabar Botanical Garden
RGCB – Rajiv Gandhi Centre for Biotechnology.
Question 25.
Why do all the food chains start from green plants?
Answer:
The basis of all food chain is the plants. They are the producers. These are eaten by the herbivores which in turn are eaten by the carnivores.
Question 26.
The members at the successive higher levels are lesser in number and larger in size in a food chain. What about their body weight? What would be the reason for that?
Answer:
In the successive higher levels in the food chain the number of consumers decreases and the size of their body increases. The number of producers will be very large. The number of animals which feed on them is less in number. But their body size increases.
Question 27.
Hay → Horse
Paddy → FowlFox
Phytoplankton → Tadpole → Fish → Man
Grass → Grasshopper → Frog → Snake → Vulture
Examine the food chain given above and classify them as primary consumers, secondary and tertiary consumers.
Answer:
Producers
Hay, Paddy, Phytoplankton, Grass
Primary consumer
Horse, Fowl, Tadpole, Grass hopper
Secondary consumers
Fox, Fish, Frog, Snake
Tertiary consumers
Vulture, Man
Question 28.
What will happen if the number of herbivores increase?
Answer:
If the number of herbivores increase they will eat away all the grass and shrubs and they will have to face shortage of food. The destruction of grass and shrubs will cause soil erosion and the top fertile soil will be washed away.
Question 29.
Animals which are facing extinction.
Answer:
- Wild goat
- Musk deer
- Indian wild Ass
- Lion tailed Monkey
- Lion
- Rhinoceros
- The large Indian Bustard
- Tiger
- Kashmir deer
- Himalayan Tiger
- Silver owl
- Panda
Question 30.
Write down the name of any two organisations that work for the protection of nature
Answer:
IUCN (International Union for
Conservation of Nature)
WWF (World Wide Fund For Nature)
Question 31.
Choose the appropriate ones from the box and complete the table
| (a) Nilgiris | i) Wild life Sanctuary |
| (b) Periyar | ii) National Parks |
| (c) Silent Valley | iii) Biosphere Reserves |
| (d) Kadalundi | iv) Community Reserve |
| (e) Malabar Botanical Garden |
Answer:
i. Wildlife Sanctuaries – b) Periyar
ii. National Parks – c) Silent Valley
iii. Biosphere reserves – a) Nilgiris
iv. Community reserves – d) Kadalundi
Question 32.
Ecological interactions and their examples are given in the boxes. Make pairs according to the model given below.
Model – Predation: Deer and tiger
| Ecological interactions | Examples |
| Predation | Mango tree and loranthus |
| Mutualism | Deer and tiger |
| Parasitism | Flower and butterfly |
| Commensalism | Mango tree and vanda |
Answer:
Predation – Deer and tiger
Mutualism – Flower and butterfly
Parasitism – Mango tree and loranthus
Commensalism – Mango tree and vanda
Question 33.
Observe the pictures
i) Identify and name the organisms given above.
ii) Mention their specific importance related to biodiversity conservation.
Answer:
(i) A. Lion – tailed macaque
(Scientic name: Macaca silenus)
B. i. Nilgiri tahr (Scientific name: Nilgiritragushylocrius)
ii) These organisms on the verge of extinction due to several reasons.
Question 34.
Analyse the given statement and answer the questions.
There exist diverse ecosystems in earth, each differs in richness of biodiversity.
i. Is it necessary to conserve all kinds of ecosystems? Why?
ii. Write any four services of biodiversity.
Answer:
a) Yes
Ecosystems are places where there is rich biodiversity. Destruction of an ecosystem means destruction of many living organisms. So, in order to protect living organisms, we have to protect natural ecosystems.
b) Availability of essential materials
- Food
- Medicine
- Fuels
- Construction materials
Cultural Services - Aesthetics
- Recreation
- Study Practice of rituals
- Ecological services
- Soil Formation
- Prevention of soil erosion.
O2, CO2 balance - Availability of freshwater
- Flood control
- Climate control
Auxiliary services - Nutrient cycling, Pollination, Biological Control. Seed dispersal
Question 35.
Give reason.
It is not possible to illustrate a food chain using the following organisms
Snake, Rat, Eagle
Answer:
Eagle feed on both rats and snakes. So we cannot illustrate food chain
Question 36.
Complete the table given below:
| A | B | C |
| Rat | Primary consumer | (a) …………………. |
| Paddy | (b) …………………. | first trophic level |
| snake | (c) ……………………. | Third trophic level |
| Eagle | Tertiary consumer | (c) …………………. |
Answer:
a) Second trophic level
b) Producers
c) Secondary consumers
d) Fourth trophic level
Question 37.
Pickout the organisms that are related to commensalism from the following and write as a pair.
Mango tree, Loranthus, Vanda, Butterfly, Snail, Flower
Answer:
Mango tree – Vanda
Question 38.
Correct mistakes if any, in the underlined part of the following statements.
• Dodo is an extinct organism.
• Palode Tropical Botanical Garden is an example for In-Situ conservation.
• Indo-Burma Region is an Ecological hotspot.
Answer:
Palode Tropical Botanical Garden is an example for Ex-situ conservation
Question 39.
Analyse the given food chain and an-swer the following.
A: Paddy → Hen → Fox → Lion
B: Grass → Deer → Tiger
a) In these food chains A and Lion and Tiger belong to which trophic levels.
b) What is the role of these organisms in maintaining ecological balance?
c) Write two messages for the conservation of these organisms, for preparing a poster.
Answer:
a) Lion – Fourth trophical level
Tiger – Third trophical level
b)They control the number of organisms that they eat. If they become extinct, the number of organism in
the lower trophic levels will be increasing in number beyond a certain limit. It will cause imbalance to the environment.
c) Earth without wild life is life without beautiful things.
If you like to shoot animals, do it with a camera, not a gun.
Question 40.
Identify the examples of given ecological interactions and answer the questions.
(i) Mango tree and Loranthus
(ii) Mango tree and Vanda
a. Name the ecological interactions (i) and (ii)
b. Write the name and peculiarity of another ecological interaction.
Answer:
a. i) Parasitism
ii) Commensalism
b. Predators – Eg: Tiger and deer
The Beauty of Diversity Class 8 Questions and Answers Notes Basic Science Chapter 16 Kerala Syllabus
Question 41.
Which trophic level has the maximum amount of energy available?
a) Primary Consumers
b) Producers
c) Secondary Consumers
d) Decomposers
Answer:
(b) Producers
Question 42.
Which interaction is characterized by the relationship where one organism benefits and the other is harmed?
(a) Mutualism
(b) Commensalism
(c) Predation
(d) Parasitism
Answer:
(d) Parasitism (Note: Predation also involves harm, but parasitism is a longterm, dependent relationship, e.g., Flea and Cat).
Question 43.
The organization responsible for publishing the Red Data Book is:
(a) WWF
(b) BMC
(c) IUCN
(d) PBR
Answer:
(c) IUCN (International Union for Conservation of Nature)
Question 44.
A Purple Frog (Mahabali Frog) is often called a ‘living fossil’ primarily because:
(a) It is found only in the Himalayas.
(b) It comes out only once a year to mate.
(c) It has undergone very little evolutionary change over millions of years.
(d) It lives underground.
Answer:
(c) It has undergone very little evolutionary change over millions of years.
Question 45.
Define Biodiversity Hotspot
Answer:
Biodiversity Hotspot: A geographically rich area that harbors a large number of endemic species and is under threat from human activities.
Question 46.
Differentiate between In-situ and Ex-situ conservation.
Answer:
In-situ Conservation: Protecting organisms within their natural habitats (e.g., National Park). Ex-situ Conservation: Protecting organisms outside their natural habitats in controlled conditions (e.g., Zoological Garden).
Question 47.
What is the main role of the Fungus component in the symbiotic relationship of a Lichen?
Answer:
The Fungus provides structure, protection, and helps in the absorption of water for the lichen organism.
Question 48.
Why is the amount of available energy found to decrease at successive trophic levels?
Answer:
Energy is lost as heat at each transfer step between trophic levels as organisms use energy for respiration and metabolic processes.
Question 49.
Explain the concept of Ecosystem Diversity with an example.
Answer:
Ecosystem Diversity: This refers to the variety of different habitats, ecosystems, and ecological processes found in an area.
Example: The diversity of hills, rivers, mangrove forests, and paddy fields found within a single region.
Question 50.
Differentiate between Genetic Diversity and Species Diversity. (2 points each)
Answer:
Genetic Diversity:
Variations within the individuals of a single species.
Example: Different varieties of rice or mango. Species Diversity:
Species Diversity.
The variety and number of different species in a particular area.
Example: The difference between a forest containing elephants, tigers, and bamboo plants.