Same chapter3 marksDifficulty: Medium
What is a mutation? State one example in human beings.
Genetics
3 marksDifficulty: Medium
Explain sex determination in human beings.
Original Khojo Papers practice question — not from a past board paper.
Answer
A human female has two X chromosomes and produces ova that all carry an X. A human male has one X and one Y and produces two kinds of sperm, half carrying X and half carrying Y. If an X-bearing sperm fertilises the ovum the child is a girl; if a Y-bearing sperm does so the child is a boy.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
The sex of the child is therefore decided by the father's gamete, not the mother's.
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