CBSE Class 10 Science 2022 · Paper 31/2/1 · Question 10

(a) Men produce two types of gametes (sperms): sperms carrying an X chromosome ($22+\text{X}$) and sperms carrying a Y chromosome ($22+\text{Y}$). (b) No. A male child (XY) inherits his Y chromosome from his father and his X chromosome from his mother. The mother (XX) can pass on only an X, so the son’s Y must come from the father’s Y-bearing sperm; had the father passed on his X, the child would be XX, a girl. (c) One type: every egg (ovum) of a human female carries an X chromosome ($22+\text{X}$).