Biodiversity and ConservationNEET MCQs with solutions

Not quite — the answer is C.

The rivet-popper hypothesis compares species in an ecosystem with rivets in an aeroplane. Removing a few rivets may not immediately cause failure, but continued species loss can impair ecosystem functioning. The trap is confusing species with genetic diversity or trophic levels.

Not quite — the answer is B.

A biodiversity hotspot is identified using both exceptional endemism and substantial loss of original habitat. Species richness alone is insufficient to qualify a region as a hotspot. The attractive trap is treating any species-rich ecosystem as a hotspot.

Not quite — the answer is D.

Among the Evil Quartet, habitat loss and fragmentation is identified as the most important cause of biodiversity loss. Over-exploitation, alien invasion and co-extinction are also major causes, but they are not the NCERT-identified foremost cause.

Not quite — the answer is A.

NCERT explicitly identifies habitat loss and fragmentation as the single most important cause of biodiversity loss globally, primarily driven by deforestation and land conversion for agriculture.

Not quite — the answer is D.

Co-extinction refers to the loss of a species caused by the extinction of another species it depends upon — a classic example is the obligate mutualism between fig trees and their species-specific fig wasps.

Not quite — the answer is C.

NCERT specifically cites the introduction of Nile perch into Lake Victoria as responsible for driving more than 200 species of native cichlid fishes to extinction — a textbook example of alien species-driven biodiversity loss.

Not quite — the answer is A.

NCERT defines biodiversity as variability among living organisms encompassing genetic diversity within species, species diversity between species, and ecosystem diversity among ecosystems. The other options describe ecological or morphological categories not used in this framework.

Not quite — the answer is B.

Genetic diversity refers to variation in genes within a species population; thousands of rice varieties cultivated across India is the NCERT example. Option A represents species diversity; Option C represents ecosystem diversity.

Not quite — the answer is C.

Ecosystem diversity refers to variety of habitats, communities and ecological processes in a region. Genetic diversity is within-species; species richness counts species, not habitat types.

Not quite — the answer is B.

Humboldt described the general increase in species richness with increasing area. NCERT expresses this as S = CA^z, where C is a constant and z is the regression coefficient (slope). Species richness does not decrease with area, is not independent of it, and latitude is a separate pattern.

Not quite — the answer is A.

Sacred groves protect biodiversity within natural habitats and therefore represent in-situ conservation. Seed banks, zoological parks and cryopreservation maintain organisms or germplasm outside natural habitats and are ex-situ methods.

Not quite — the answer is D.

Genetic diversity is variation within a species. Different rice varieties illustrate intraspecific genetic variation. Differences among species represent species diversity, while differences among ecosystems represent ecosystem diversity. Trophic levels are an ecological concept unrelated to genetic diversity.

Not quite — the answer is C.

Lantana camara is a notorious alien invasive species introduced into India that outcompetes native flora. Alien species invasion is one of the four major causes of biodiversity loss listed in the Evil Quartet, alongside habitat loss, over-exploitation and co-extinction.

Not quite — the answer is C.

Genetic diversity occurs within species, exemplified by different rice varieties. Species diversity concerns different species in a region, while ecosystem diversity concerns variation among distinct ecosystems such as forests, deserts and wetlands.

Not quite — the answer is D.

Species-rich communities contain organisms performing complementary ecological roles, which can buffer ecosystems against disturbances. However, high richness does not eliminate competition or guarantee against extinction.

Not quite — the answer is A.

In situ conservation protects species within their natural habitats including wildlife sanctuaries, national parks, and biosphere reserves. Ex situ removes species from their habitat. Seed banks and biosphere reserves alone are narrower categories under the broader in situ umbrella.

Not quite — the answer is C.

National parks protect species within their natural habitats and are the primary example of in situ conservation per NCERT. Zoological parks, seed banks, and cryopreservation facilities all maintain species outside natural habitats, making them ex situ methods.

Not quite — the answer is B.

Ex situ conservation protects species outside their natural habitats in botanical gardens, zoos, seed banks, and cryopreservation facilities. In situ conservation and habitat restoration both work within or toward natural environments; natural selection is not a conservation strategy.

Not quite — the answer is B.

NCERT states species diversity is highest near the equator and decreases progressively toward the poles — this pattern is called the latitudinal gradient in species diversity.

Not quite — the answer is B.

When both S and A are plotted on logarithmic scale, the species-area relationship becomes a straight line. Z is the slope of this line (regression coefficient), indicating the rate at which species richness increases with area.

Not quite — the answer is D.

NCERT provides S = CAᶻ where S is species richness, A is area, C is the Y-intercept constant and Z is the regression coefficient (slope). Option C inverts the relationship incorrectly.

Not quite — the answer is A.

Narrowly utilitarian value covers direct economic uses of biodiversity including food, fibre, fuel wood, and medicines obtained directly from biological resources.

Not quite — the answer is B.

Broadly utilitarian value refers to indirect benefits provided by biodiversity through ecosystem services like pollination, nutrient cycling, and atmospheric regulation. Narrowly utilitarian value is limited to direct economic uses only.

Not quite — the answer is C.

Ethical value is rooted in the idea that humans co-inhabit the planet with millions of species, each with an intrinsic right to exist irrespective of economic or ecological benefit to humans.