Suppose that gene "b" is sex-linked, recessive and lethal. A man marries a woman who is heterozygous for this gene. If this couple had many normal children, what would be the projected sex ratio of the children?
Sex-Linked?
It may be 2 girls: 1 boy because the Punnett square for this cross would show 2 normal girls: 1 normal boy: 1 affected boy. Since they had many normal children, then they didn't get any of the affected boys. That leaves 2 girls: 1 boy.
Reply:they would probably have more girls than boys
possible 2 girls and 1 boy I think
I guess the gene must be one the X chromosome, so the girls would have 2 chances not to get the gene (because they have 2 chromosomes, and one is used as a barr body) and the boys they had must have gotten lucky and received mom's dominant X chromosome
Reply:If the gene was sex-linked and lethal, then statistically, half of the male children should die. That would leave you with a ratio of 2 girls to 1 boy.
sensitive teeth
No comments:
Post a Comment