Question

2. A certain recessive, lethal gene is carried on the X chromosome. (Lethal genes are those that result in death.) A man marries a woman who is hybrid for this gene. What sex ratio would be expected among the living children of this couple?
%Male
%Female​
Please help me im stuck!

Answer 1

The surviving children would be 66.7% female and 33.3% male. Of the female children, 50% would be expected to be carriers of this gene (like their mother)
| Xg | X
—————-
X | XXg | XX
—————-
Y | XgY | XY

Pretty ugly, but the best punnet square I can do without a link. The offspring with the “g” are those that carry the lethal gene. The male child that carries it will die, but since it is recessive, the female child will live but will be a carrier for this gene. I hope this helps.