Science Group
Explore subjects and practice MCQs
10
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1,000
Total MCQs
Unit-10 Evolution
Answer: Adaptations are inherited characteristics that increase an organism's chances of survival and reproduction in its habitat.
Answer: Individuals with favourable traits survive and reproduce more, so those traits become more common over generations.
Answer: Camouflage helps the chameleon hide from predators and also to ambush prey, improving its survival.
Answer: Without genetic variation there is nothing for natural selection to act upon, so evolution cannot occur.
Answer: Overhunting and destruction of habitat drove dodos and passenger pigeons to extinction.
Answer: Cacti have long roots and succulent stems that store water, adapting them to dry desert conditions.
Answer: Thick fur and fat layers insulate polar bears against the extreme cold of their Arctic environment.
Answer: The similar underlying bone structure of these forelimbs is evidence that all mammals share a common ancestor.
Answer: The generally accepted sequence of human ancestors runs from Australopithecus through Homo habilis and Homo erectus to Homo sapiens.
Answer: Extinction is the permanent loss of a species when its last individuals die out.
Answer: Modern humans belong to the species Homo sapiens.
Answer: Comparative anatomy compares the body structures of different organisms to find evidence of evolution.
Answer: Evolution is essentially a change in the inherited traits or gene frequencies of a population over time.
Answer: Before industrial pollution darkened tree trunks, light-coloured peppered moths were camouflaged and more common.
Answer: Very similar protein or DNA sequences indicate a recent common ancestry between the species.
Answer: On pollution-darkened trees the dark moths were better camouflaged, so predators ate fewer of them.
Answer: Vestigial organs are reduced remnants that had functions in ancestors but are not useful in the present organism.
Answer: Overproduction creates competition, variation provides differences, struggle follows, and the fittest survive.
Answer: Evolution holds that all living organisms share common ancestors, so life arises from pre-existing life over long periods.
Answer: The similar early embryonic stages of fish, birds, mammals, and reptiles indicate a shared ancestor.