A scientist measured the height of 200 adult humans in a population. The results showed a normal distribution curve with most individuals close to the mean height. Which statement best explains this pattern?

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Question

A scientist measured the height of 200 adult humans in a population. The results showed a normal distribution curve with most individuals close to the mean height. Which statement best explains this pattern?

Accepted Answer

Height is controlled by many genes and is influenced by the environment — Award 1 mark for recognising that continuous variation producing a normal distribution is caused by polygenic inheritance plus environmental factors. A is incorrect — single genes produce discontinuous variation. C is incorrect — the normal distribution indicates continuous variation. D is incorrect — height has a strong genetic component.

Answer

Height is controlled by a single gene with two alleles

Answer

Height is determined only by environmental factors

Answer

Height shows discontinuous variation

Answer

Height is controlled by many genes and is influenced by the environment

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