In humans, brown eye color dominates over blue. The heterozygous brown-eyed parents have a blue-eyed daughter. What eye color can grandchildren have if a daughter marries a heterozygous brown-eyed man? And if he is homozygous brown-eyed?
In the first case, 1/2 of the grandchildren will have brown eyes, and 1/2 will have blue eyes. In the second, all grandchildren will be brown-eyed.
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