Environmental Studies · Biology

Biodiversity and Conservation

2,266 Questions

Biodiversity and conservation questions address threats to ecosystems, climate change impacts, and habitat loss. These topics are essential for environmental science sections in major competitive exams. Practicing these questions clarifies concepts regarding species extinction and ecological management.

Habitat loss consequencesClimate change impactsEcosystem degradation causesDesert biodiversity threatsForest diversity threatsResource extraction effects

Biodiversity and Conservation Questions

Multiple choice botany energy flow in an ecosystem biogeochemical cycle nutrient cycles species, communities and ecosystems

If all decomposers are removed from an ecosystem, what will happen?

  1. All consumer will die

  2. Energy cycle will be inverted

  3. Balance of biogeochemical cycle will be disturbed

  4. Only herbivores will die
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Decomposers are saprotrophs, which decompose the organic remains by secreting extracellular digestive enzymes. Due to degradation of organic remains, decomposers are also called as reducers. They are also known as mineralisers as they release minerals trapped in organic remains. Detrivores are decomposers as well as scavengers, e.g., earthworm. Decomposition of organic wastes and dead and decaying plants and animals returns the minerals locked in living systems back to the environment. Thus, decomposition is very important for the biogeochemical cycles, or nutrient cycling.

Multiple choice botany energy flow in an ecosystem biogeochemical cycle nutrient cycles species, communities and ecosystems

If wild animals are killed, what difficulty would we face?

  1. Imbalance in nature

  2. Decrease in fog rain

  3. Decrease in population

  4. Increase in rain
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Killing wild animals disrupts food chains and food webs, causing ecological imbalance. Predators control prey populations, and their removal can lead to overpopulation of certain species and collapse of ecosystem dynamics.

Multiple choice biology main natural resources classification of threatened species red data book methods of conservation

The Red Data Book records

  1. Species diversity of wet lands

  2. List of water pollutants

  3. List of threatened species

  4. Rate of population decline
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The International Union for Conservation of Nature is an international organization which works in the area of the conservation of nature and sustainable use of natural resources. The Red Book is a state document which is established for documenting rare and endangered species of animals, plants, and fungi, as well as some local subspecies. The species (including animals, plants, fungi, etc.) which are vulnerable to endangerment in the near future are known as threatened species. IUCN treats threatened species as a group of three categories, depending on the degree relative to which they are threatened. Those categories are Vulnerable species; Endangered species and Critically endangered species. 

So, the correct answer is 'List of threatened species'.

Multiple choice biology main natural resources classification of threatened species red data book methods of conservation

............. is the taxon, which is likely to move into endangered category in near future, if conditions prevail as it is.

  1. Vulnerable

  2. Endanger

  3. Rare

  4. Extinct
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Endangered species is a species facing a high risk of extinction in the wild in the near future due to a decrease in its habitat, excessive predation or poaching.
Vulnerable species are those for which presently the population is sufficient but is undergoing depletion due to some factors so that it is facing the risk of extinction in a medium term.
Rare species are species with naturally small populations, either localized or thinly scattered.
Extinct species are the taxon completely eliminated or died out from Earth, e.g., Dodo.

Multiple choice biology main natural resources classification of threatened species red data book methods of conservation

According to IUCN Red List, during the last two decades, the maximum increase in the number of threatened species is among

  1. Mammals

  2. Amphibians

  3. Reptiles

  4. Birds
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
According to the IUCN Red List, during the last two decades, the maximum increase in the number of threatened species is among amphibians as some groups like amphibians appear to be more vulnerable to extinction. More than 15,500 species worldwide are facing the threat of extinction. Presently, 12 percent of all bird species, 23 percent of all mammal species, 32 percent of all amphibian species and 31per cent of all gymnosperm species in the world face the threat of extinction.
So, the correct answer is 'Amphibians'.
Multiple choice evs forests and life forest - the dwelling place of animals forest and its importance introduction to forests conservation of forest and wildlife wildlife

When we destroy a forest we destroy 

  1. An ecosystem

  2. The plant life

  3. Population of wild life

  4. Food and shelter of wild animals
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

An ecosystem is a complex network of living organisms and their physical environment. Destroying a forest removes the entire system of interactions, not just the plants or animals individually.

Multiple choice zoology our environment - our concern biomagnification the effects of human activities on ecosystems bioaccumulation and biomagnification

A fish-eating bird species was found to have a specific, heavy metal concentration of 700,000 ppt (parts per trillion). The conclusion based on the data is

  1. Air pollution may have caused this bird species to inhale dangerous amounts of heavy metals while migrating.

  2. The entire population of the bird species, from which this sample was taken, died.

  3. The population of this bird species exploded, causing an ecosystem imbalance.

  4. Pollutants tend to collect in areas of land where this bird species nests.

  5. This bird species is at a high trophic level on the food chain.
Reveal answer Fill a bubble to check yourself
E Correct answer
Explanation

Organisms at higher trophic levels in a food chain can experience biomagnification, which is the accumulation of environmental toxins (such as heavy metals) in living tissue. Organisms at lower trophic levels accumulate small amounts of toxins through their food. Because organisms at the next highest trophic level eat many of the lower-level organisms, they take in higher amounts of the toxins. At the highest trophic levels, increased concentrations of toxins in organisms’ tissues can be dangerous. This bird tissue has a high concentration of a specific heavy metal, so the species must be at a high trophic level. Therefore, the correct answer is option E.

Multiple choice zoology our environment - our concern biomagnification the effects of human activities on ecosystems bioaccumulation and biomagnification

Multiple Choice Questions
Biomagnification of DDT causes decline in bird population by

  1. Disturbing Ca metabolism

  2. Thinning of egg shells

  3. Premature breaking of egg shells

  4. All the above.
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation
Biomagnification refers to an increase in concentration of toxic substances due to its accumulation at successive trophic levels. Biomagnification of DDT disturbs calcium metabolism in birds leading to thinning of eggshells and its premature breaking. It also leads to a significant decrease in their population.
So, the correct answer is option D, all the above.
Multiple choice biology main natural resources classification of threatened species red data book conservation of wildlife

A taxon facing an extremely high risk of extinction in wild in the near future is called as

  1. Critical endangered

  2. Endangered

  3. Vulnerable

  4. Extinct in wild
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Extinct: A species those having no living members.
Endangered: A species those are facing high risk of extinction in the wild in near future.
Critically endangered:  A taxon is critically endangered when it is facing an extremely high risk of extinction in the wild in the immediate future.
Vulnerable: A taxon is vulnerable when it is not critically endangered or endangered but is facing a high risk of extinction in the medium-term future.
Thus, the correct answer is option B.

Multiple choice biology main natural resources classification of threatened species red data book conservation of wildlife

Which of the following species is very near to extinction, if conservation measures are not promptly taken?

  1. Threatened species

  2. Rare species

  3. Endangered species

  4. Vulnerable species
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Endangered species is a species facing a high risk of extinction in the near future due to a decrease in its habitat, excessive predation or poaching e.g., Ailurus fulgens (Red Panda), Bentinckia nicobarica. 

Some other examples are Blue Whale, Asiatic wild ass and Lion-tailed Macaque.
Vulnerable species are those for which presently the population is sufficient but is undergoing depletion due to some factors so that it is facing the risk of extinction in the medium term.
Rare species are species with naturally small populations, either localised or thinly scattered.
Threatened species include critically endangered, endangered and vulnerable.
Therefore, the correct answer is option C.

Multiple choice biology main natural resources classification of threatened species red data book conservation of wildlife

Animals get extinct mainly due to

  1. Predation

  2. Habitat destruction

  3. Afforestation

  4. Pollution
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Habitat destruction is the process in which natural habitat is rendered functionally unable to support the species present. In this process, the organisms that previously used the site are displaced or destroyed, reducing biodiversity. Habitat destruction by human activity is mainly for the purpose of harvesting natural resources for industry production and urbanization. Clearing habitats for agriculture is the principal cause of habitat destruction. Other important causes of habitat destruction include mining, logging, trawling and urban sprawl. Habitat destruction is currently ranked as the primary cause of species extinction worldwide.

Therefore, the correct answer is option B.

Multiple choice biology main natural resources classification of threatened species red data book conservation of wildlife

Species with low population numbers that are in considerable danger of elimination are termed as 

  1. Endemic

  2. Extinct

  3. Endangered species

  4. Evolution
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
  1. A species whose habitat is restricted to a particular area is known as endemic species. 
  2. A species that has died out and hence is out of site is called extinct species.
  3. A species which is less in number and can be extinct in near future is called endangered species.
  4. The origination and development of new life forms on earth is called evolution.
Thus the correct answer is option 'Endangered species'.
Multiple choice biology main natural resources classification of threatened species red data book conservation of wildlife

Introduction of alien species into new area poses a threat to extinction of indigenous species due to 

  1. their high nutrient requirement

  2. their symbiotic relationship

  3. absence of their natural predators

  4. more intraspecific competition.
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

In the absence of their natural predators, exotic species flourish better and pose a threat to indigenous species.

Multiple choice biology main natural resources classification of threatened species red data book conservation of wildlife

The extinction of passenger pigeon was due to 

  1. increased number of predatory birds.

  2. over exploitation by humans.

  3. non-availability of the food

  4. bird flu virus infection.
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The passenger pigeon or wild pigeon (Ectopistes migratorius) is an extinct species of pigeon that was endemic to North America. Its common name is derived from the French word passager, meaning "passing by", due to the migratory habits of the species. The scientific name also refers to its migratory characteristics. The morphologically similar mourning dove (Zenaida macroura) was long thought to be its closest relative, and the two were at times confused, but genetic analysis has shown that the genus Patagioenas is more closely related to it than the Zenaida doves. The main reasons for the extinction of the passenger pigeon were the massive scale of hunting, the rapid loss of habitat, and the extremely social lifestyle of the bird, which made it highly vulnerable to the former factors. Deforestation was driven by the need to free land for agriculture and expanding towns, but also due to the demand for lumber and fuel. Though there are still large woodland areas in eastern North America, which support a variety of wildlife, it was not enough to support the vast number of passenger pigeons needed to sustain the population.  As the flocks dwindled in size, the passenger pigeon population decreased below the threshold necessary to propagate the species.

So the correct option is 'over exploitation by humans'.