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: Y-linked inheritance principle.
Y chromosome genes are passed solely from father to son due to exclusive male inheritance of the Y chromosome.
Step 2: Inheritance pattern.
- Sons receive the Y chromosome from their father, inheriting all Y-linked genes.
- Daughters receive the X chromosome from their father, precluding Y-linked trait inheritance.
Step 3: Evaluation of possibilities.
- All sons: Accurate.
- All daughters: Inaccurate; daughters inherit only X chromosomes.
- Half of sons: Inaccurate; all sons inherit the Y chromosome.
- Half of daughters: Inaccurate; daughters never inherit the Y chromosome.
Step 4: Final determination.
Consequently, a male with a Y-linked gene transmits it to all his sons.