Choose the correct answer from the four options given below:
In a human male, a sperm will contain:
Topic: Chromosomes in a sperm
Try it
Pick an option and check your answer. The full worked answer is below either way.
Answer
(d) Either X or Y chromosome.
A single sperm carries EITHER an X OR a Y chromosome — never both.
THE REASON: a male body cell is XY. During MEIOSIS the homologous pair separates, one member going to each gamete. So half the sperms produced carry X and half carry Y, but each individual sperm has only ONE sex chromosome.
Option (a) is the trap, and it confuses the BODY cell with the GAMETE. The father’s body cells are XY; his sperms are X or Y.
THE CONSEQUENCE: since every ovum carries X, it is the sperm that decides the sex of the child — X sperm gives XX (girl), Y sperm gives XY (boy) — and the chance is 50:50 at every conception.
Either X or Y chromosome.