Science Group
Explore subjects and practice MCQs
10
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Total MCQs
Unit-10 Evolution
Answer: Variations are the differences that exist among individuals of the same species, which are important for natural selection.
Answer: These structures are vestigial remnants left over from evolutionary ancestors and have lost their original functions.
Answer: Variation provides the raw material on which natural selection can act, favouring some individuals over others.
Answer: Embryology studies embryos; similar early embryos of different vertebrates provide evidence of common ancestry.
Answer: Fossils of Australopithecus are considered among the earliest known human ancestors that walked upright.
Answer: Similarities in early embryonic stages among diverse vertebrates point to a shared evolutionary ancestry.
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Answer: Overproduction means that organisms produce more offspring than the environment can support, leading to competition.
Answer: The more similar the DNA or protein sequences of two organisms, the more recently they likely shared a common ancestor.
Answer: Homo habilis, meaning 'handy man', is associated with the earliest stone tools.
Answer: Because of overproduction, individuals compete for limited resources, which is called the struggle for existence.
Answer: Individuals with advantageous variations are better able to survive and reproduce, passing these traits to offspring.
Answer: Molecular data such as DNA sequences provide the most direct evidence of evolutionary relatedness.
Answer: Natural selection is often described as survival of the fittest, where the best-adapted individuals survive.
Answer: The main difference is the selecting agent: humans in artificial selection and the environment in natural selection.
Answer: Bat and bird wings share a similar bone pattern inherited from a common ancestor, so they are homologous.
Answer: Geographical isolation separates populations, allowing them to evolve independently and eventually form new species.
Answer: Fossils are the preserved remains or impressions of organisms from past geological ages.
Answer: Geographical isolation by physical barriers prevents interbreeding, leading to independent evolution and possibly speciation.
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Answer: Convergent evolution causes unrelated species to develop similar adaptations when exposed to similar environments.
Answer: The fossil record shows a sequence of organisms that lived at different times, supporting the idea of change over time.