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Question
A study found that children with light-coloured eyes are likely to have parents with light-coloured eyes. On this basis, can we say anything about whether the light eye colour trait is dominant or recessive? Why or why not?
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Solution
This information is not sufficient. It is unclear from the provided information whether light eye colour is recessive or dominant. Nonetheless, given that both the parents and the offspring have light-coloured eyes, it's possible that this feature is recessive. Only homozygous light-eyed parents would have light-eyed offspring if light eye colour had been a dominant feature, but heterozygous light-eyed parents might have had some recessive dark-eyed children (three to one ratio).
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|
(e) |
(f) |
||
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