CBSE Class 12 Biology Biodiversity and Conservation Assignment Set A

Biodiversity : Term used to describe diversity at all levels of biological organisation. Term coined by socio-biologist Edward Wilson and was also used by Walter G Rosen for the diversity of life forms. Biodiversity refers to totality of genes in species and ecosytems of a region.

Three inter-related levels of Biodiversity : Genetic diversity, Species diversity, Ecological diversity.

• Genetic diversity : Diversity in the number and types of genes, as well as chromosomes present in different species and the variations in the genes and their alleles in the same species. It helps in speciation.

• Species diversity : Varieties in the number and richness of the species of a region.

• Ecological diversity : Variety in the types of ecosystems.

IUCN : International Union for Conservation of Nature and Natural Resources. It is situated in Morges, Switzerland.

India has : More than 50,000 genetically different varieties of rice; 1000 varieties of mango;

• India has 1,42,000 known species of plants and animals (Around 45,000 species of plants and rest of animals);

• India has 8.1% of share of global biodiversity.

• India is one of 12 Mega diversity countries of the world. Latitudinal Gradients

• In general, species diversity decreases as we move away from the equator towards the poles.

• With very few exceptions, tropics (latitudinal range of 23.5¢X N to 23.5¢XS) harbour more species than temperate or polar areas. 

Important Questions for NCERT Class 12 Biology Biodiversity and Conservation

Question. Which among the following is the criterion for determination of 'Biodiversity hot spot' -
(a) Very high level of species richriess
(b) High degree of habitat loss and fragmentation
(c) High degree of Endemism
(d) All of the above

Answer : D

Question. Pattern of Biodiversity depends upon -
(a) Latitudinal gradient
(b) Altitudinal gradient
(c) Species - area relationship
(d) All of these

Answer : D

Question. From 'The Evil Quartet' which of the following is most important cause of biodiversity loss -
(a) Habitat loss and fragmentation
(b) Over - exploitation
(c) Alien species invasion
(d) Co-extinctions

Answer : A

Question. In India, how many genetically different strains of rice and mango varieties are present -
(a) <50,000 and 1,0000 respectively
(b) 1000 and 50000 respectively
(c) >50.000 and 1.000 respectively
(d) >50,000 and 5,000 respectively

Answer : C

Question. Find out incorrect statement -
(a) Biodiversity exists at all levels of biological organisation
(b) A single species cannot show more diversity at genetic level
(c) Western ghats have a greater amphibian species diversity
(d) India has greater ecological diversity than Scandinavian country.

Answer : B

Question. The most dramatic examples of habitat loss come from tropical rain forests. Once covering more that 14 present of earths land surface and now cover no more than -
(a) 5%
(b) 6%
(c) 10%
(d) 13%

Answer : B

Question. Careful analysis of records shows that extinction across taxa are not random, some groups like ______ appear to be more vulnerable to extinction.
(a) Reptiles
(b) Mammals
(c) Aves
(d) Amphibians

Answer : D

Question. The Amazon rain forest 'lungs of Planet" harbouring probably millions of species is being cut & cleared for which purpose -
(a) For cultivation of soyabeans
(b) For conversion to grasslands for raising beef cattles
(c) For cuttivation of Medicinal plants
(d) Both (a) and (b)

Answer : D

Ques. The Indian rhinoceros is a natural inhabitant of which one of the Indian states?
(a) Uttarakhand
(b) Uttar pradesh
(c) Himachal Pradesh
(d) Assam

Answer: D

Ques. Which one of the following has maximum genetic diversity in India?
(a) Mango
(b) Wheat
(c) Tea
(d) Teak

Answer: A

Ques. Which one of the following pairs of organisms are exotic species introduced in India?
(a) Lantana camara, water hyacinth
(b) Water hyacinth, Prosopis cinereria
(c) Nile perch, Ficus religiosa
(d) Ficus religiosa, Lantana camara 

Answer: A

Ques. One of the endangered species of Indian medicinal plants is that of
(a) Ocimum
(b) garlic
(c) Nepenthes
(d) Podophyllum. 

Answer: D

Ques. Which of the following pairs of an animal and a plant represents endangered organisms in India?
(a) Banyan and black duck
(b) Bentinckia nicobarica and red panda
(c) Tamarind and rhesus monkey
(d) Cinchona and leopard 

Answer: B

Ques. According to IUCN Red List, what is the status of Red Panda (Ailurus fulgens)?
(a) Critically endangered species
(b) Vulnerable species
(c) Extinct species
(d) Endangered species 

Answer: D

Ques. Which group of vertebrates comprises the highest number of endangered species?
(a) Mammals
(b) Fishes
(c) Reptiles
(d) Birds 

Answer: A

Ques. Which endangered animal is the source of the world’s finest, lightest, warmest and most expensive wool – the shahtoosh?
(a) Nilgai
(b) Cheetal
(c) Kashmiri goat
(d) Chiru 

Answer: D

Ques. Wildlife is continuously decreasing. What is the main reason of this?
(a) Predation
(b) Cutting down of forest
(c) Destruction of habitat
(d) Hunting 

Answer: C

Ques. Indri-indri lemur is found in
(a) Madagascar
(b) Mauritius
(c) India
(d) Sri Lanka. 

Answer: A

Ques. Occurrence of endemic species in South America and Australia is due to
(a) these species has been extinct from other regions
(b) continental separation
(c) there is no terrestrial route to these places
(d) retrogressive evolution. 

Answer: B

Ques. Which of the following is mainly responsible for the extinction of wildlife?
(a) Pollution of air and water
(b) Hunting of flesh
(c) Destruction of habitats
(d) All of these 

Answer: C

Ques. What is the major cause of diminishing wildlife number?
(a) Felling of trees
(b) Paucity of drinking water
(c) Cannibalism
(d) Habitat destruction 

Answer: D

Ques. The breeding place of Flamingo (Hansawar) in India is most likely
(a) Runn of Kutch
(b) Ghana Vihar
(c) Sambhar lake
(d) Chilka lake. 

Answer: D

Ques. The abundance of a species population, within its habitat, is called
(a) relative density
(b) regional density
(c) absolute density
(d) niche density. 

Answer: D

Ques. The most important human activity, leading to the extinction of wildlife, is
(a) pollution of air and water
(b) hunting for valuable wildlife products
(c) introduction of alien species
(d) alteration and destruction of the natural habitats. 

Answer: D

Ques. The Earth Summit held in Rio de Janeiro in 1992 was called
(a) for immediate steps to discontinue use of CFCs that were damaging the ozone layer
(b) to reduce CO₂ emissions and global warming
(c) for conservation of biodiversity and sustainable utilisation of its benefits
(d) to assess threat posed to native species by invasive weed species. 

Answer: C

Very Short Answer Type Questions

Question. What accounts for the greater ecological diversity of India?
Answer : The greater ecological diversity of India is because of the geographical diversity in terms of varying topography, e.g., deserts, rain forests, mangroves, coral reefs, wetlands, estuaries and alpine meadows all are present in India. This results in building of different varieties of ecosystems with greater ecological diversity.

Question. Explain as to how protection of biodiversity hot spots alone can reduce up to 30% of the current rate of species extinction.
Answer : The biodiversity hot spots are regions with very high level of species richness, especially those under threat from humans, thus their protection can reduce the current rate of extinction. These regions can be protected as biological reserves, national parks and sanctuaries.

Question. What is the difference between endemic and exotic species?
Answer : Endemic species are native or indigenous species, which are restricted to a particular geographical region. Exotic or alien species are those species which are introduced from one geographical region to another geographical area. Exotic species may lead to disappearance of native species.

Question. How does species diversity differ from ecological diversity?
Answer : Species diversity refers to the number and distribution of species in an area. It is expressed in terms of ‘number of species per unit area’ and also as number of individuals of different species in an area. Ecological diversity refers to the diversity at ecosystem level. It is related to different types of ecosystem habitats e.g., terrestrial (forests, grasslands, etc.) and aquatic (freshwater and marine) ecosystems.

Question. What characteristics make a community stable?
Answer : The characteristics that make a community stable are
(i) Less variation in productivity from year to year.
(ii) Resistance or resilience to occasional disturbances (natural or man-made).
(iii) Resistance to invasions by alien species.

Question. Define the terms (i) Bioprospecting (ii) Endemism
Answer : (i) Bioprospecting is a term that describes the process of discovery and commercialisation of new products based on biological resources.
(ii) Endemism refers to presence of some species in particular regions only and now here else

Question. What is common to the species shown in figures A and B?
Answer : Both are angiospermic flowering plants.

Question. According to David Tilman, greater the diversity, greater is the primary productivity. Can you think of a very low diversity man-made ecosystem that has high productivity? K Thinking Process Artificial or anthropogenic ecosystem are man-made terrestrial or aquatic ecosystems. The most important are agriculture field, generally called as agroecosystems.
Answer : The man-made ecosystems like agricultural field of paddy or wheat show very low diversity, but possess high productivity. These are also an example of monoculture.

Short Answer Type Questions

Question. Is it possible that productivity and diversity of a natural community remain constant over a time period of, say one hundred years?
Answer : No, it is not possible that productivity and diversity of a natural community remain constant over a certain time period. This is because
(i) The natural habitat is never maintained in real.
(ii) Abundant resources are never available, they are always in short supply or just enough.
(ii) Environmental conditions for survival and reproduction are continuously changing.

Question. There is greater biodiversity in tropical/subtropical regions than in temperate region. Explain.
Answer : The tropical/subtropical region exhibit maximum biological diversity because these region remain undisturbed due to less variable climatic conditions. So, tropics had a longer evolutionary time for species diversification. The temperate environment are more seasonal, less constant and unpredictable, therefore less niche specialisation and lesser species diversity are observed.

Question. Of the four major causes for the loss of biodiversity (Alien species invasion habitat loss and fragmentation, over-exploitation and co-extinctions) which according to you is the major cause for the loss of biodiversity ? Give reasons in support.
Answer : Out of the four major causes for the loss of biodiversity, loss of habitat and fragmentation is the major cause as (i) Habitat loss and fragmentation caused by clearing and over-exploitation of forest areas for agriculture, urbanisation and industrialisation, results in destruction of natural habitats. (ii) Increasing human population has overburdened the forest resources and have destroyed forest land, which means loss of habitat for several species. (iii) In addition, large habitats are broken up into small fragments, because of which mammals and birds requiring large territories and migratory habits are badly affected, leading to decline inpopulation.

Question. How do scientists extrapolate the total number of species on earth ?
Answer : There are two methods to estimate and extrapolate the number of species on earth
(i) The primary method used by the scientists to extrapolate the number of species on earth is the estimation rate of discovery of new species.
(ii) Total number of species can also be extrapolated by the statistical comparison of the tropical and temperate species richness of exhaustively studied groups of insects. The ratio is then extrapolated with existing species of plants and animals to predict the gross estimate of the number of species on earth.

Question. Humans benefit from diversity of life. Give two examples.
Answer : (i) Humans derive numerous economic benefits directly from diversity of organisms.
(a) Food products (cereals, pulses and fruits).
(b) Firewood.
(c) Fibre (cotton, jute from plants and silk, wool from animals).
(d) Construction material (timber for making furniture, houses and sports goods).
(e) Industrial products (tannins, lubricants, dyes, resins and perfumes).
(f) Products of medicinal importance (about 25000 plants are used in traditional medicine).
(ii) There are huge intangible benefits that humans derive from the diversity of life.
(a) Pure oxygen.
(b) Natural pollinators.
(c) Flood and soil erosion control.
(d) Nutrient replenishment.
(e) Waste recycling by microbes and other insects, etc.
(f) Aesthetic pleasure and mental peace.

Question. List any two major causes other than anthropogenic causes of the loss of biodiversity.
Answer : The two major causes other than anthropogenic causes of the loss of biodiversity are
(i) Alien Species Invasions When alien species are introduced unintentionally or deliberately in a habitat, some of them can cause decline or extinction of indigenous species.
(ii) Co-extinctions When a species becomes extinct, the plant and animal species associated with it, in an obligatory way, also become extinct.

Question. What is an endangered species? Give an example of an endangered plant and animal species each?
Answer : An endangered species is a population of organisms, which is facing a high risk of becoming extinct because
(i) Its number being very low.
(ii) It is threatened by changing environment.
(iii) It is facing predator threat. Endangered plant species-Venus fly trap Endangered animal species-Siberian tiger

Question. What are sacred groves and their role in biodiversity conservation?
Answer : Sacred groves are sacred tracts which are held in high esteem by local communities. The sacred groves are dedicated to local deities or ancestral spirits and are protected by local communities through social traditions and taboos that incorporate spiritual and ecological values. Sacred groves represent native vegetation in a natural or near natural state and are thus, rich in biodiversity and harbour many rare species of plants and animals. Such sacred groves are found in Meghalaya (Khasi and Jaintia hills), Aravalli hills of Rajasthan, Western Ghats, regions of Karnataka and Maharashtra and Madhya Pradesh (Bastar, Chanda and Sarguja region).

Question. Suggest a place where one can go to study coral reefs, mangrove vegetation and estuaries.
Answer : Places to be suggested for studying coral reefs-Andaman and Nicobar Islands. Mangrove vegetation-Paschim Banga Sunderban, Estuaries-Coastal areas of Karnataka.

Question. Where would you expect more species biodiversity— in tropics or in polar regions? Give reasons in support of your answer
Answer : More biodiversity is found in the tropics. This is because tropical regions remain undisturbed from frequent glaciations as in polar regions. Also, the tropics are less seasonal/more constant.

Question. “Stability of a community depends on its species richness.” Write how did David Tilman show this experimentally.
Answer : David Tilman found that plots with more species showed less year-to-year variation in total biomass. He also showed that in his experiments, increased diversity contributed to higher productivity.

Question. State the use of biodiversity in modern agriculture. 
Answer : Biodiversity is a source of hybrids, GM plants, biopesticides, organic farming, biofertiliser, improved varieties of plants, disease resistant plants. (Any two)

Question. In the biosphere immense biological diversity exists at all levels of biological organisation.
Explain any two levels of biodiversity. 
Answer :  
- The occurrence of different types of genes, gene pools, species, habitats and ecosystems in a particular place and various parts of earth is called biodiversity.
- The term ‘biodiversity’ was given by Edward Wilson.
- Biodiversity is divided into three levels of biological organisation:
(i) Genetic diversity
- It is the measure of variety in genetic information contained in the organisms over its distributional range.
- It enables a population to adapt to its environment.
- For example, medicinal plant Rauwolfia vomitoria growing in Himalayan ranges shows variation in potency and concentration of the active chemical reserpine that it produces.
- There are more than 50,000 genetically different strains of rice and 1,000 varieties of mango in India.
(ii) Species diversity
- It is a measure of the variety of species and their relative abundance present within a region.
- For example, the Western Ghats have a greater amphibian species diversity than the Eastern Ghats.
(iii) Ecological diversity
-OU It is a measure of the diversity at community and ecosystem levels. They represent the local, unique habitat and regional components of species diversity.
OU For example, ecological diversity is greater in India than a Scandavian country like Norway due to presence of large number of ecosystems like deserts, rainforests, coral reefs, wetlands, estuaries and alpine meadows.

Question.Seeds of different genetic strains are kept for long periods in seed banks. Explain the conservative strategy involved in this process. 
Answer : The strategy is called Ex-situ conservation. In this technique, seeds are preserved in viable and fertile condition for long periods using cryopresrvation techniques. 

Question. Why are sacred groves highly protected? 
Answer : Sacred groves are highly protected because of religious and cultural traditions. These are refuges for large number of rare and threatened plants. They are ecologically unique and biodiversity rich regions.

Question. What is cryopreservation? Give its one use. 
Answer : Cryopreservation is a preservation technique in which sperms, eggs, cells, tissues, etc., are stored at ultra-low temperature of −196ºC under nitrogen. Cells and gametes of threatened species can also be preserved by this method.

Question. Mention the kind of biodiversity of more than a thousand varieties of mangoes in India represent. How is it possible?
Answer : Thousand varieties of mangoes represent genetic diversity.
This is possible because:
(i) Single species show high diversity at genetic level over its distributional range.
(ii) Different varieties grow in different geographical areas.
(iii) Mutations.

Question. Which region/biome in the world is considered as the ‘Lungs of the planet’? Give two reasons for its degradation.
Answer : The Amazon rain forests are considered as the lungs of the planet. They are cut and cleared for cultivation of soya beAnswer : Some part has been converted into grass lands for raising beef cattle.

Question. State how does ex-situ conservation help in protecting biodiversity.
Answer :  
- This approach involves placing threatened animals and plants in special care units for their protection.
- India has 35 botanical gardens and 275 zoological parks where animals which have become extinct in wild are maintained.
- By using cryopreservation (preservation at –196°C) technique, sperms, eggs, animal cells, tissues and embryos can be stored for long period in genes banks, seed banks, etc.
- Plants are propagated in vitro using tissue culture methods (micropropagation).
- It is the desirable approach when urgent measures to save extinction are required.
Differences between in situ conservation and ex situ conservation

In situ conservation	Ex situ conservation
It is the conservation and protection of biodiversity in its natural habitat.	It is the conservation of selected threatened plant and animal species in places outside their natural habitat
Population is conserved in the surroundings where they have developed their distinctive features.	Population is conserved under simulated conditions that closely resemble their natural habitats.
E.g., national parks, biosphere reserves, wildlife sanctuaries, etc.	E.g., botanical gardens, zoological parks,wildlife safari, gene banks, etc.

Question. List any four techniques where the principle of ex situ conservation of biodiversity has been employed. 
Answer : Cryopreservation, in vitro fertilisation, micropropagation/tissue culture, sperm bank/seed bank/gene bank.

Question. Assess the effects of loss of biodiversity in a region. Mention any four such effects.
Answer : (i) Decline in plant production and animal species.
(ii) Lowered resistance to environmental perturbations such as drought.
(iii) Increased variability in certain ecosystem processes such as plant productivity/water use/ pest and disease cycles.
(iv) Increased rate of species extinction.

Long Answer Type Questions

Question. Describe the consumptive use value of biodiversity as food, drugs and medicines, fuel and fibre with suitable examples.
Answer : Biological resources are the basis of life forms on this planet. The countries with maximum biodiversity possess better potential to compete with the rest of the world. Biodiversity has great economic importance to mankind due to its many uses, some of, which with consumptive value are following Food is obtained from biodiversity sources like livestock, forestry and fish. Biodiversity in modern agriculture is beneficial due as a source of new crops. e.g., just three cereals crop like wheat, rice and maize account for about 55% of protein and 60% of calories in humAnswer : Drugs such as morphine (Papaver somniferum), quinine (Cinchona ledgeriana), reserpine (Rauwolfia vomitaria), belladonna (Atropa belladonna), aconite (Aconitum, napellus), wintergreen and birth bark (Gaultheria procumbens) are derived from plants. About 70-80% of entire population is dependent on plants or its extract for medicine. penicillin (Penicillium notatum), tetracycline (bacteria), digitalin (Digitalis) are some examples of medicinal plants. Plant like Chorchorus, Gossypium are sources of fibre while Jatropha is a source of biofuels. Fossils fuels (e.g., petrolum) are obtained from fossils of organisms.

Question. Elaborate how invasion by an alien species reduces the species diversity of an area.
Answer : When alien species are introduced unintentionally or deliberately in a habitat, some of them can cause decline or extinction of indigenous species, e.g., extensive environmental damage caused and threat posed to our native species by invasive weed species like carrot grass (Parthenium), Lantana and water hyacinth (Eichhornia). Another example of exotic species invasion is Nile perch, a large predator fish. When this alien species was introduced into lake of Victoria in East Africa, it started feeding on native, cichlid fish. As a result indigenous cichlid fish became extinct and due to scarcity of food, predator Nile perch died too.

Question. How can you, as an individual, prevent the loss of biodiversity?
Answer : Biodiversity is the occurrence of different type of species, habitat, ecosystem, gene, genepool in a particular place and various parts of earth. As an individual, biodiversity can be conserved with conservation strategies and management of both biotic and abiotic resources.
Some of the conservation strategies are as follows
(i) Protection of useful animals and plants in their natural habitat or in situ conservation.
(ii) Preservation of critical habitats like feeding and breeding areas and resting area of endangered species to promote their growth and multiplication.
(iii) Hunting should be banned or regulated.
(iv) Habitat of migratory animals should be protected by bilateral or multilateral agreements.
(v) People should be made aware of the importance of biodiversity and its conservation.
(vi) Over exploitation of natural resources must be avoided.
(vii) Biodiversity plays an important role in maintaining and sustaining supply of goods and services.
(viii) Conservation of biodiversity ensures well being of all the living creatures and their future generations.

Question. Species diversity decreases as we move away from the equator towards the poles. What could be the possible reasons?
Answer : Species diversity decreases as we move towards the poles, because (i) Temperature decreases and conditions become harsh. (ii) Both the amount and intensity of solar radiation decreases. (iii) Vegetation decreases. (iv) Less resources available to support species. Speciation is generally a function of time and environmental stability, so if conditions are too harsh, it is difficult for the species to survive and adapt. This results in decrease in biodiversity towards the poles.

Question. Explain briefly the ‘rivet popper hypothesis’ of Paul Ehrlich.
Answer : Ecologist Paul Ehrlich gave rivet popper hypothesis to help understand the contribution species richness. He compared each species with rivet in the body of an airplane. (i) This hypothesis explains that ecosystem to be an airplane and the species to be the rivets joining all parts together.
(ii) If every passenger travelling in the airplane start taking rivets home (causing a species to become extinct), initially it may not affect flight safety (proper functioning of ecosystem), but over a period of time the plane becomes weak and dangerous (species become endangered and then extinct.

Question. Explain ‘rivet popper’ hypothesis. Name the ecologist who proposed it. 
Answer : Paul Ehrlich proposed the rivet popper hypothesis. This hypothesis states that in an airplane (ecosystem) all parts are joined together using thousands of rivet (species). If every passenger travelling in it starts popping a rivet to take home (causing a species to become extinct), it may not affect flight safety (proper functioning of the ecosystem) initially but as more and more rivets are removed, the plane becomes dangerously weak over a period of time. Also, which rivet is removed may also be critical like loss of rivets on the wings (key species) is more serious threat to flight safety than loss of few rivets on the seats or windows inside the plane.

Question. ‘In situ’ conservation can help endangered/threatened species. Justify the statement.
Answer : In ‘in situ’ conservation threatened organisms are conserved in their natural habitat or ecosystem, and such regions are legally protected. This has been carried out by identifying certain regions as hotspots, biosphere reserves, national parks, sanctuaries, sacred groves and Ramsar sites. 
This approach involves protection of species in their natural habitat.
(a) Biodiversity hotspots
- These are regions of high levels of species richness and high degree of endemism.
- Endemic species are species confined only to a limited region.
- There are 34 hotspots in the world.
- In India, the three hotspots are Western Ghats and Sri Lanka, Indo–Burma and Himalaya.
- Biodiversity hotspots cover less than 2% of earth’s land area, but they harbour large number of species. Thus, they could reduce mass extinction by 30%.
(b) Protected areas
- India has 14 biosphere reserves, 90 national parks and 448 wildlife sanctuaries.
- Jim Corbett National Park was the first to be established in India.
(c) Ramsar sites
- Ramsar sites are wetlands which are considered to be of international importance.
- Ramsar Convention (1971) is an international treaty for the conservation and sustainable utilisation of wetlands.
- Ramsar convention works for (a) conservation and use of wet lands, (b) recognition of fundamental ecological functions of wetlands and their cultural, economic, scientific and recreational value.
- There are 26 Ramsar sites in India. Some of these are Ashtamudi wetland (Kerala), Sambhar lake,Rudrasagar lake, Chilika lake, Bhitakanika wetland (Odisha).
- Wetlands include marshes, lakes, coral reefs, etc.
(d) Sacred groves
- These are forest patches set aside for worship. All the trees and wildlife within are given total protection by tribal people.
- Large number of rare and threatened plants can be found in these regions.
- Some of the sacred groves in India are as follows:
— Khasi and Jaintia Hills in Meghalaya
— Western Ghat regions of Karnataka and Maharashtra
— Aravalli Hills of Rajasthan
— Sarguja, Chanda and Bastar areas of Madhya Pradesh.

 QUESTIONS

1. Habitat loss and fragmentation has caused severe damage to a particular type of ecosystem. Name it.

2. What trend is observed in respect of species diversity when we move from equator to poles?

3. Which region is considered as the one with highest biodiversity on earth? What is the name given to such region.forests?

4. Ecologists have discovered that value of lies in range of 0.1 to 0.2 regardless of taxonomic group or region. When will the slope of line steeper in species area relationship?

5. Define cryopreservation. Why is it useful in conserving biodiversity?

6. What is the reason for genetic variation shown by medicinal plant Rauwolfia vomitoria?

7. How many species of plants and animals have been described by IUCN in 2004? What is global species diversity according to Robert May?

8. Explain co-extinction with a suitable example.

ANSWERS

1. Tropical Rain Forest.

2. In general, species diversity decreases as we move away from the equator towards poles.

3. Amazonian rain forests. They are also called the ‘Lungs of the planet’.

4. Slope of line is much steeper if one analyses the species¡Varea relationship among very large areas like entire continents.

5. Preserving a material in liquid nitrogen at – 196°C. It can be done to preserve threatened species in viable and fertile condition for long period.

6. Genetic variation might be in terms of potency and concentration of the active chemical reserpine produced by plant.

Please refer to attached file for CBSE Class 12 Biology Biodiversity and Conservation Assignment Set A