In humans, brown eye color and the ability to better control the right hand are inherited as dominant traits. A brown-eyed young man who has better control of his right hand, homozygous for both characteristics, marries a blue-eyed left-hander. Determine: 1) what kind of offspring can be expected from this marriage; 2) what phenotype can grandchildren have from a marriage of a son with a woman who has the characteristics of his mother, and a daughter with a man who has the characteristics of her father.
Let’s designate the dominant and recessive alleles of the genes: A – brown eye color, a – blue color, B – right-handedness, b – left-handedness.
1) Offspring from marriage – brown-eyed right-handers;
2) a) grandchildren from a son – brown-eyed right-handers, brown-eyed left-handers, blue-eyed right-handers, blue-eyed left-handers in a ratio of 1: 1: 1: 1;
b) grandchildren from a daughter – brown-eyed right-handers.
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