Question

A man who carries a harmful sex-linked gene on his X chromosomes will pass the gene to

a. All of his daughters
b. Half of his daughters
c. All of his sons
d. Half of his sons
e. All of his children

Answer 1

A man with a harmful sex-linked gene on his X chromosome will pass the gene to all of his daughters, making them carriers of the condition.

Step-by-step explanation:

When considering sex-linked genes, particularly those on the X chromosome, it is important to understand how they are passed down from parents to offspring. In human genetics, males have one X and one Y chromosome (XY), while females have two X chromosomes (XX).

A man with a harmful sex-linked gene on his X chromosome can only pass this chromosome to his daughters because males always pass the Y chromosome to their sons, which determines the male sex. Therefore, all of his daughters will inherit this X chromosome and be carriers of the gene, although they will typically not express the disorder unless it is dominant or they inherit another X with the same gene from their mother.