Question

A man carries a gene on his Y chromosome; he will transmit this gene to which of the following?

• A. All his sons
• B. All his daughters
• C. Half of his sons
• D. Half of his daughters

Hint:

Y-linked inheritance = father → all sons, never daughters.

Answer 1

The Correct Option is A

Step 1: Recall Y-linked inheritance.
Genes present on the Y chromosome are transmitted exclusively from father to son, as only males inherit the Y chromosome.
Step 2: Transmission logic.
- Sons inherit the Y chromosome from their father, so all sons will receive Y-linked genes.
- Daughters inherit the X chromosome from their father, not the Y. Hence, daughters cannot inherit Y-linked traits.
Step 3: Checking the options.
- All sons: Correct.
- All daughters: Wrong, daughters inherit X only.
- Half of sons: Wrong, all sons inherit Y.
- Half of daughters: Wrong, daughters never inherit Y.
Step 4: Conclusion.
Thus, a man carrying a Y-linked gene transmits it to all his sons.