Biodiversity and Conservation Exam Questions Class 12 Biology

Please see Chapter 15 Biodiversity and Conservation Exam Questions Class 12 Biology below. These important questions with solutions have been prepared based on the latest examination guidelines and syllabus issued by CBSE, NCERT, and KVS. We have provided Class 12 Biology Questions and answers for all chapters in your NCERT Book for Class 12 Biology. These solved problems for Biodiversity and Conservation in Class 12 Biology will help you to score more marks in upcoming examinations.

Exam Questions Chapter 15 Biodiversity and Conservation Class 12 Biology

Statement Type Questions

Question. Best way to preserve the wild life is
(a) to kill the predators.
(b) vaccinize the animals.
(c) to preserve natural habitat.
(d) optimize the breeding habit.

Question. Which of the following is done in a wild life sanctuary?
(a) conservation of fauna
(b) conservation of flora
(c) utiliation of soil and flora
(d) prohibition of hunting

Question. Which one of the following shows concept of speciesarea relationship?
(a) The number of species in an area increases with the size of the area.
(b) Larger species require larger habitat areas than do smaller species.
(c) Most species within any given area are endemic.
(d) The larger the area, the greater the extinction rate.

Question. Which of the following is not a step in understanding biodiversity?
(a) Naming the species
(b) Looking at other related species
(c) Assessing the species geographic range
(d) Quantifying the species genome

Question. Sacred groves are found in
(a) Khasi and Jaintia Hills in Meghalaya.
(b) Aravalli Hills of Rajasthan.
(c) Western ghat regions of Karnataka and Maharashtra and Sarguja, Chanda and Bastar areas of Madhya Pradesh.
(d) All of the above

Question. Biodiversity loss occurs due to the reasons given below.
(i) Habitat loss and fragmentation
(ii) Co-extinction
(iii) Over-exploitation
(iv) Alien species invasion
Identify the correct reasons.
(a) (i) and (ii)
(b) (i), (ii) and (iii)
(c) (ii), (iii) and (iv)
(d) (i), (ii), (iii) and (iv)

Assertion/Reason Type Questions

In the following questions, a statement of Assertion is followed by a statement of Reason.
(a) If both Assertion and Reason are true and the Reason is the correct explanation of the Assertion.
(b) If both Assertion and Reason are true but the Reason is not the correct explanation of the Assertion. 
(c) If Assertion is true but Reason is false.
(d) If both Assertion and Reason are false.

Question. Assertion: Communities that comprise of more species tend to be more stable.
Reason: A higher number of species results in less animal variation in total biomoss.

Question. Assertion: The presently occurring species extinction is different from the mass extinctions that have occurred earlier.
Reason : Extinction in present day is due to natural causes, whereas earlier it was due to man-made causes.

Question. Assertion: Diversity observed in the entire geographical area is called gamma diversity.
Reason : Biodiversity decreases from high altitude to low altitude.

Matching Type Questions

Question. Match column-I with column-II and choose the correct option.

Column-I	Column-II
A. Nile Perch in Lake	I. Obvious reasons for Victoria biodiversity conservation
B. Narrowly utilitarian	II. Habitat destruction
C. Main cause for	III. High endemism biodiversity loss
D. Hotspots	IV. Alien species

(a) A – II, B – I, C – IV, D – III
(b) A – IV, B – I, C – II, D – III
(c) A – I, B – III, C – II , D – IV
(d) A – II, B – I, C – III, D – IV

Question. Match column -I with column- II and choose the correct option.

Column-I	Column-II
A. Biodiversity	I. Edward Wilson
B. In-situ conservation	II. Co-extinction
C. Plant pollinator mutualism	III. On-site conservation
D. Ex-situ conservation	IV. Off-site conservation

(a) A – II, B – I, C – IV, D – III
(b) A – IV, B – I, C – II, D – III
(c) A – I, B – III, C – II , D – IV
(d) A – II, B – I, C – III, D – IV

Question. Match the following and then choose the correct option.

Column-I	Column-II
A. Endemism	I. Khasi and Jaintia hills Meghalaya
B. Hotspot of India	II. Advanced ex-situ conservation
C. Sacred groove	III. Species found in a particular area only
D. Cryopreservation	IV. Zoological park and Botanical gardens
E. Ex-situ conservation	V. Western Ghats

(a) A – III, B – V, C – I, D – II, E – IV
(b) A – I, B – II, C – III, D – IV, E– V
(c) A – II, B – III, C – IV, D – V, E – I
(d) A – V, B – I, C – IV, D – II, E – III

Question. Match the following and choose the correct option.

Column-I	Column-II
A. Narrowly utilitarian	I. Conserving biodiversity argument for major ecosystem services
B. Broadly utilitarian	II. Conserving biodiversity argument for philosophical or spiritual need to realise that every species has intrinsic value and moral duty to pass our biological legacy in good order to future generation.
C. Ethical argument	III. Conserving biodiversity for direct economic benefits like food, medicine, industrial products etc.

(a) A – I, B – II, C – III
(b) A – III, B – I, C – II
(c) A – II, B – I, C – III
(d) A – I, B – III, C – II

Question. Match the following and choose the correct option.

Column-I	Column-II
A. Over-exploitation by humans	I. Environmental damage  and threat to native species
B. Introduction of Nile Perch in Lake Victoria	II. Decline in plant  population
C. Less solar energy	III. Extinction of more than 2000 species of native birds
D. Introduction of Water Hyacinth in India	IV. Extinction of Cichlid fish
E. Colonization of tropical pacific  Islands	V. Extinction of Passenger pigeon

(a) A – II, B – V, C – IV, D – III, E – I
(b) A – V, B – IV, C – II, D – I, E – III
(c) A – I, B – II, C – III, D – IV, E – V
(d) A – IV, B – I, C – II, D – V, E – III

Diagram Type Questions

Question. Using the figure, determine the percentage of bird species that will be lost if the island’s inhabitable land area is reduced from 100,000 km² to 1 km².

(a) 17 percent of the bird species will be lost.
(b) 20 percent of the bird species will be lost.
(c) All of bird species will be lost.
(d) 93 percent of the bird species will be lost.

Critical Thinking Questions

Question. Following arrangement is correct from the point of view of decreasing biodiversity in angiosperms (N), fungi (F), pteridophytes (P) and algae (A).
(a) N > F > P > A
(b) N > F > A > P
(c) F > N > P > A
(d) F > N > A > P

Question. If S is species richness, A is area, Z is slope of the line, and the C is Y-intercept, then the species richness will be shown as
(a) S = C + Az
(b) S = C + AZ
(c) S = C. AZ
(d) S = C. Az

Question. A threatened species category includes
(a) only endangered species.
(b) only vulnerable species.
(c) endangered and rare species.
(d) endangered, vulnerable and rare species.

Question. Animal species should be preserved mainly because
(a) zoologists want to study them.
(b) they are lovely creatures.
(c) they are useful to mankind.
(d) man cannot recreate a species of animals after its destruction.

Question. All forms of life should be conserved because
(a) they maintain diverse genetic resources.
(b) they have economic values.
(c) they are important for maintaining balance of nature.
(d) they will be otherwise lost.

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

Question. The greatest threat to global biodiversity is
(a) natural disasters such as storms
(b) pollution
(c) overexploitation of natural resources
(d) alteration of habitats by humans

Question. Biosphere reserves differ from national parks and wildlife sanctuaries because in the former
(a) human beings 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.

Very Short Answer Questions

Question. What is genetic diversity?
Ans. It is the measure of variation in genetic information contained in the organisms.

Question. What is mass extinction?
Ans. Due to natural calamities like volcanic eruptions, prolonged drought, heavy rains, earthquakes, asteroid collision, etc., a large number of species become extinct at the same time which is called mass extinction.

Question. Identify ‘a’ and ‘b’ in the figure given below representing proportionate number of major vertebrate taxa.
Ans. a → Mammals
b → Amphibians

Question. Name the three important components of biodiversity.
Ans. The three important components of biodiversity are: genetic diversity, species diversity and ecological diversity.

Question. India has more than 50,000 strains of rice. Mention the level of biodiversity it represents.
Ans. 50,000 strains of rice represent genetic biodiversity.

Question. Name the unlabelled areas ‘a’ and ‘b’ of the pie chart (given alongside) representing the global biodiversity of invertebrates showing their proportionate number of species of major taxa. 
Ans. a → Insects;
b → Molluscs

Short Answer Questions

Question. Assess the effects of loss of biodiversity in a region. Mention any four such effects.
Ans. (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.

Question. Narrowly utilitarian arguments are put forth in support of biodiversity conservation. Explain the other two arguments that are put forth in support of the same cause. 
Ans. Broadly utilitarian arguments
OU Biodiversity plays a major role in maintaining and sustaining supply of goods and services from various species as well as ecological systems.
OU The different ecological services provided are:
Ethical reasons
OU There are thousands of plants, animals and microbes on this earth which are not useless. Every one has some intrinsic value even if it is not of any economic value to us.
OU It is, therefore, our moral duty to ensure well-being of all the living creatures for the utilisation of future generations.

Question. State how does ex-situ conservation help in protecting biodiversity.
Ans. Ex situ conservation (Off-site conservation)
QU This approach involves placing threatened animals and plants in special care units for their protection.
QU India has 35 botanical gardens and 275 zoological parks where animals which have become extinct in wild are maintained.

Question. Differentiate between in situ and ex situ approaches of conservation of biodiversity.
Ans. 

S.No.	In situ conservation	Ex situ conservation
(i)	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.
(ii)	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.
(iii)	E.g., national parks, biosphere reserves, wildlife sanctuaries, etc.	E.g., botanical gardens, zoological parks, wildlife safari, gene banks, etc.

Question. Seeds of different genetic strains are kept for long periods in seed banks. Explain the conservative strategy involved in this process. 
Ans. 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. Discuss one example, based on your day-to-day observations, showing how loss of one species may lead to extinction of another. 
Ans. In case a species becomes extinct, the plant and animal species associated within an obligatory way also become extinct. For example,
(i) When a fish species which is a host for a number of parasites becomes extinct, the parasite species which are uniquely dependent on the host fish will also become extinct.
(ii) The insects may be polyphagous (feed on more than one plant species) or monophagous (feed on only one particular plant species) in nature. The monophagous insect species are valuable and may become extinct if the plant species upon which it feeds becomes extinct.

Question. How is biodiversity important for ecosystem functioning?
Ans. Importance of biodiversity for ecosystem functioning:
(i) Stability: Biodiversity is an important aspect for stability of an ecosystem. Ecologists believe that communities with more species tend to be more stable than those with less species.
(ii) Productivity: Ecosystem with higher biodiversity show more productivity than ecosystems with lower biodiversity. David Tilman’s long-term ecosystem experiments using outdoor plots provide confirmation.
(iii) Ecosystem health: Rich biodiversity is not only essential for ecosystem health but imperative for the survival of the human race on earth. Species are interlinked and so, killing or disappearance of one would effect the others also.
(iv) Resilience: Increased biodiversity provides resilience of the ecosystem against natural or man-made disturbances.

Question. Justify with the help of an example where a deliberate attempt by humans has led to the extinction of a particular species. 
Ans. When Nile perch, a large predator fish, was introduced in Lake Victoria, it started feeding on the native fish, Cichlid fish. As a result, Cichlid fish became extinct and Nile perch, not finding any food for itself, died too.

Question. The species diversity of plants (22 per cent) is much less than that of animals (72 per cent).
What could be the explanations to how animals achieved greater diversification?
Ans. Animals have achieved greater diversification than plants due to following reasons:
(i) They are mobile and thus can move away from their predators or unfavourable environments.
On the other hand, plants are fixed and have fewer adaptation to obtain optimum amount of raw materials and sunlight therefore, they show lesser diversity.
(ii) Animals have well-developed nervous system to receive stimuli against external factors and thus can respond to them. On the other hand, plants do not exhibit any such mechanism, thus, they show lesser diversity than animals.

Long Answer Questions

Question. Alien species are highly invasive and are a threat to indigenous species. Substantiate this statement with any three examples.
Ans. Exotic species are defined as species that have been introduced from another geographic region to an area outside its natural range. For example,
(i) Parthenium, Lantana and Eichhornia are the exotic species of plants that have invaded the native species of India and caused environmental damage.
(ii) Introduction of African catfish Clarias gariepinus for aquaculture purpose is posing threat to many indigenous catfish.
(iii) Nile perch introduced into lake Victoria in East Africa led to the extinction of cichlid fish.

Question. The graph shows species-area relationship:

(a) If b denotes the relationship on log scale-
(i) Describe a and b.
(ii) How is slope represented? Give the normal range of slope.
(iii) What kind of slope will be observed for frugivorous birds and mammals in a tropical forest?
(b) Species diversity of plants (22%) is much less than that of animals (72%). Analyze the reasons for greater diversity of animals as compared to plants.
Ans. (a) (i) a is S = CA2

b is log S = log C + Z log A
(ii) Slope is Z (regression coefficient). Its normal value ranges from (iii) In frugivorous birds and mammals, value of Z=1.15
(b) Reasons for greater diversity of animals are:
(i) Animals are mobile and can avoid predator or unfavourable event.
(ii) Well developed nervous system to receive stimuli against external factors and respond to them.

Question. The given graph alongside shows species–area relationship. Write the equation of the curve ‘a’ and explain. 
Ans. The equation of the curve ‘a’ is S = CAZ.
(i) Within a region, species richness increases with increasing explored area but only up to a limit.
(ii) Relationship between species richness and area for a wide variety of taxa turns out to be rectangular hyperbola.

Question. (a) Why should we conserve biodiversity? How can we do it?
(b) Explain the importance of biodiversity hotspots and sacred groves. 
Ans. (a) • Biodiversity is important for ecosystem health and for survival of human race on earth. There are
three main reasons for conserving the biodiversity which have been classified into the following categories:
(i) Narrowly utilitarian arguments
• Human beings derive direct economic benefits from nature, like food, firewood, fibre, construction material, industrial products (resins, gums, dyes, tannins, etc.) and medicinally important
products.
• More than 25 per cent of the drugs are derived from plants and about 25,000 species of plants are used by native people as traditional medicines.
(b) Conservation of Biodiversity
• Biodiversity can be conserved by protecting its whole ecosystem.
• There are two basic approaches for conservation of biodiversity.
(i) In situ conservation (On site conservation)
This approach involves protection of species in their natural habitat.