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100 questions in this collection · Page 8 of 10
Question 71 of 100
📘 CLASS XII
Biodiversity And Conservation
Evaluate the level of genetic and species diversity within India:
I. India has more than 50,000 genetically different strains of rice. II. India has 1,000 genetically different varieties of mango. III. The Western Ghats have a greater amphibian species diversity than the Eastern Ghats.
Which of the statements given above are correct?
All three statements are correct. India possesses over 50,000 genetically different strains of rice, about 1,000 varieties of mango, and the Western Ghats have higher amphibian diversity than the Eastern Ghats.
Question 72 of 100
📘 CLASS XII
Biodiversity And Conservation
Study the species diversity statistics documented for the Amazon rain forest:
I. It is home to more than 40,000 species of plants and 3,000 species of fishes. II. It harbors 1,300 species of birds, 427 species of mammals, and 427 species of amphibians. III. It is home to 378 species of reptiles and more than 1,25,000 species of invertebrates.
Which of the options represents the correct statistics?
All three statements are correct and match the NCERT statistics for the Amazonian rain forest.
Question 73 of 100
📘 CLASS XII
Biodiversity And Conservation
With reference to "The Evil Quartet", match the invasive introduction with its corresponding ecological damage:
I. Nile perch introduction – Extinction of more than 200 species of cichlid fish in Lake Victoria. II. Illegal introduction of African catfish (Clarias gariepinus) – Threat to indigenous catfishes in Indian rivers. III. Introduction of Carrot grass (Parthenium) – Completely eradicated all aquatic invasive weeds in Indian wetlands.
Which of the pairings given above are correct?
Statements I and II are correct. Statement III is incorrect because Parthenium is itself an invasive terrestrial weed and has not eradicated aquatic invasive weeds.
Question 74 of 100
📘 CLASS XII
Biodiversity And Conservation
Consider the comparisons of mass extinction episodes in Earth's history:
I. There were five episodes of mass extinction of species before humans appeared on Earth. II. The "Sixth Extinction" currently in progress is estimated to be 10 to 20 times slower than previous episodes due to modern conservation efforts. III. Human activities are directly responsible for the accelerated rates of the current sixth mass extinction.
Which of the statements given above are correct?
Statements I and III are correct. Statement II is incorrect because the present extinction rate is estimated to be 100 to 1,000 times faster than the pre-human background rate.
Question 75 of 100
📘 CLASS XII
Biodiversity And Conservation
Read the following statements regarding the categorization of conservation arguments:
I. Exploring molecular, genetic, and species-level diversity for products of economic importance is called bioprospecting. II. Bioprospecting belongs to the broadly utilitarian category because it involves genetic engineering. III. The ethical argument states that every species has an intrinsic value, even if it has no current economic value to us.
Which of the statements given above are correct?
Statements I and III are correct. Bioprospecting is a narrowly utilitarian concept because it focuses on products of direct economic importance. The ethical argument emphasizes the intrinsic value of every species.
Question 76 of 100
📘 CLASS XII
Biodiversity And Conservation
Analyze the following statements concerning the mathematical properties of the species-area relationship:
I. In the logarithmic equation log S = log C + Z log A, the parameter log C represents the slope of the regression line. II. When analysis is restricted to small, local areas within a single region, the value of the regression coefficient (Z) lies within a remarkably consistent range of 0.1 to 0.2 regardless of the taxonomic group. III. Over massive continental scales, the regression line becomes much steeper, resulting in Z values shifting to the range of 0.6 to 1.2. IV. For frugivorous birds and mammals in the tropical forests of different continents, the slope of the line is specifically found to be 1.15.
Which of the statements given above are correct?
Statement I is incorrect because Z is the slope (regression coefficient), whereas C is the Y-intercept. Statements II, III and IV are correct. For local studies, Z ranges from 0.1 to 0.2, for continental analyses it ranges from 0.6 to 1.2, and for frugivorous birds and mammals in tropical forests the value is about 1.15.
Question 77 of 100
📘 CLASS XII
Biodiversity And Conservation
Read the following statements regarding the taxonomic and biological exclusion of prokaryotes from global species estimates:
I. Conventional taxonomic methods are highly suitable and standardly used to isolate, catalog, and name microbial species. II. Many prokaryotic species are simply not culturable under laboratory conditions. III. If biochemical or molecular criteria are accepted for delineating species, prokaryotic diversity might run into millions.
Which of the statements given above are correct?
Statement I is incorrect because conventional taxonomic methods are not suitable for identifying microbial species. Statements II and III are correct since many prokaryotes cannot be cultured under laboratory conditions and molecular criteria suggest their diversity may run into millions.
Question 78 of 100
📘 CLASS XII
Biodiversity And Conservation
Study the following statements regarding the quantitative species counts recorded in the Amazonian rain forest:
I. The Amazonian rain forest is home to more than 40,000 species of plants. II. It harbors exactly 1,300 species of fishes and 3,000 species of birds. III. It is home to 427 species of mammals and 427 species of amphibians. IV. It harbors 378 species of reptiles and more than 1,25,000 species of invertebrates.
Which of the statements given above are correct?
Statement II is incorrect because the figures are reversed. The Amazon harbors about 3,000 species of fishes and 1,300 species of birds. Statements I, III and IV are correct.
Question 79 of 100
📘 CLASS XII
Biodiversity And Conservation
Consider the bird species richness at different latitudes to evaluate the latitudinal gradient of biodiversity:
I. Colombia, located near the equator, has nearly 1,400 species of birds. II. India, with much of its land area in tropical latitudes, has more than 1,200 species of birds. III. Greenland at 71° N has only 105 species, while New York at 41° N has 56 species of birds.
Which of the statements given above are correct?
Statement III is incorrect because New York has about 105 bird species, whereas Greenland has only about 56. Statements I and II correctly illustrate the latitudinal gradient of biodiversity.
Question 80 of 100
📘 CLASS XII
Biodiversity And Conservation
With reference to David Tilman's long-term ecosystem stability experiments, study the following statements:
I. Tilman's experiments used outdoor plots to understand species richness and ecosystem stability. II. He discovered that plots with more species showed greater year-to-year variation in total biomass. III. He demonstrated that in his experiments, increased diversity contributed to higher productivity.
Which of the statements given above are correct?
Statement II is incorrect because plots with greater species richness showed less year-to-year variation in total biomass. Statements I and III are correct.