CBSE Class 12 (Science) Biodiversity and Conservation — practice questions
90 free MCQs with worked solutions. Tap any question for the answer + explanation, or practice them all in the app.
Practice CBSE Class 12 (Science) Biodiversity and Conservation in the app →Which of these is a terrestrial ecosystem?Which is a man-made ecosystem?The basic energy input to any ecosystem is:Green plants in an ecosystem are called:Animals that feed directly on plants are:Producers belong to which trophic level?Energy movement through trophic levels is:The rate of biomass production is called:GPP minus respiration losses equals:The rate at which consumers form new organic matter is:The annual net primary productivity of the biosphere is about:Raw material for decomposition is called:Which is NOT a step of decomposition?Plants capture what share of photosynthetically active radiation?Decomposition is slower when detritus is rich in:Which conditions favour decomposition?The mass of living material at a trophic level is the:The pyramid of biomass in the sea is generally:Which ecological pyramid can never be inverted?Which group is left out of ecological pyramids?Which sociobiologist popularised the term biodiversity?The potency of reserpine in Rauwolfia across the Himalaya shows which diversity?About how many genetically different rice strains does India have?How many varieties of mango are cited for India as genetic diversity?The Western Ghats having more amphibian species than the Eastern Ghats shows what?India has deserts, mangroves, coral reefs and alpine meadows. This shows high what?According to IUCN (2004), roughly how many species have been described so far?Robert May's conservative estimate of global species diversity is about what?Of all species recorded so far, which group makes up more than 70 per cent?Plants including algae and fungi form no more than what share of recorded species?Which animal group is the most species-rich on earth?Out of every 10 animals on this planet, how many are insects?Why is the number of prokaryotic species so uncertain?India has about 2.4 per cent of world land area. What share of global species does it hold?India is counted among how many mega diversity countries of the world?If May's estimate holds, what share of all species has been recorded so far?What is the general trend of species diversity from the equator to the poles?Which latitudinal range defines the tropics in the study of diversity?Which place near the equator has about 1,400 bird species?Greenland at 71 N has only how many bird species?India, being mostly tropical, has how many bird species?Which rain forest has the greatest biodiversity on earth?Which idea explains rich tropical diversity through evolutionary time?Constant, predictable tropical climates promote greater diversity by encouraging what?Greater solar energy in the tropics is linked to diversity through which factor?Which naturalist observed that species richness rises with area up to a limit?What curve shape does species richness against area follow?In log S = log C + Z log A, what does Z stand for?The species-area slope Z for smaller regions usually lies in which range?For entire continents, the species-area slope Z is found in which range?Whose long-term plot experiments linked more species to steadier biomass?Tilman found that plots with more species showed what in total biomass?The rivet popper hypothesis was proposed by which ecologist?In the rivet popper analogy, what do the rivets represent?In the rivet analogy, rivets on the wings stand for which kind of species?Human colonisation of tropical Pacific islands led to loss of how many bird species?The IUCN Red List (2004) records how many extinctions in the last 500 years?The dodo, a recently extinct bird, was native to which place?The extinct thylacine was native to which region?Which animal group appears more vulnerable to extinction than others?What share of amphibian species worldwide faces the threat of extinction?How many mass extinction episodes occurred during the history of life on earth?How does the Sixth Extinction differ from earlier mass extinctions?What is the nickname for the four major causes of biodiversity loss?Which is the most important cause driving species to extinction?Rain forests once covered over 14 per cent of land. What do they cover now?Fragmentation of large habitats badly affects which animals?The passenger pigeon went extinct mainly because of what?Which fish introduced into Lake Victoria wiped out over 200 cichlid species?Which of these is an invasive weed named as a threat to native Indian species?The African catfish Clarias gariepinus threatens Indian rivers after its introduction for what?A host fish goes extinct and so do its unique parasites. What is this called?Besides utilitarian reasons, which type of argument supports conserving biodiversity?More than what share of drugs sold worldwide come from plants?What is bioprospecting?Pollination by bees, birds and bats is an example of which argument?The idea that every species has intrinsic value belongs to which argument?Saving the whole forest to save the tiger is which approach?Biodiversity hotspots are defined by high species richness and what else?Biodiversity hotspots are also regions of what?How many biodiversity hotspots does the NCERT list for the world?All hotspots together cover less than what share of earth's land area?Sacred groves in Meghalaya are found in which hills?Which is an ex situ conservation site?Preserving gametes of threatened species for long periods uses which technique?Seeds of different genetic strains of crop plants are kept in what?The Convention on Biological Diversity (Earth Summit) was held where in 1992?The 2002 World Summit on Sustainable Development was held in which city?Who wrote about the biodiversity hotspot concept in 1988 and 1990?To qualify as a hotspot, a region must have lost at least what share of its primary vegetation?