FBISE Class 9th (SSC-l)
Explore subjects and practice MCQs
3
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Total MCQs
FBISE Class 9th (SSC-l)
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.
Answer: Molecular biology compares DNA and protein sequences; the degree of similarity reveals how closely organisms are related.
Answer: In biology, fitness means the ability to survive and reproduce in a particular environment, not physical strength.
Answer: Members of the same species share the greatest genetic similarity because they are the most closely related.
Answer: Natural selection requires variation; if all individuals are identical, selection cannot favour one over another.
Answer: Mutations are random changes in DNA that introduce new variations upon which natural selection can act.
Answer: Bacteria with genes for resistance survive antibiotic treatment and multiply, so resistant strains become common.
Answer: Fossils provide direct physical evidence that organisms lived in the past and changed over time.
Answer: Natural selection acts on existing variations, so variation is essential for evolution to occur.
Answer: Without favourable variations, individuals are less suited to their environment and more likely to die before they can reproduce.
Answer: Natural selection favours individuals with traits that improve survival and reproduction in their environment.