Sex determination in humans takes place by :-

Options

A. sex chromosomes of father
B. measurement of sperm
C. measurement of ovum
D. sex chromosomes of mother

Answer

**Step-by-Step Solution:**

1. **Understanding Chromosomes**: Humans have 23 pairs of chromosomes, which include 22 pairs of autosomes and 1 pair of sex chromosomes. The sex chromosomes determine the biological sex of an individual.

2. **Identifying Sex Chromosomes**: In humans, females have two X chromosomes (XX), while males have one X and one Y chromosome (XY).

3. **Gamete Formation**: During reproduction, females produce ova (egg cells) that always carry an X chromosome. Males produce sperm cells that can carry either an X or a Y chromosome.

4. **Fertilization Process**: When fertilization occurs, the sex of the offspring is determined by the type of sperm that fertilizes the egg:
- If a sperm carrying an X chromosome fertilizes the egg (which always carries an X), the result is a female (XX).
- If a sperm carrying a Y chromosome fertilizes the egg, the result is a male (XY).

5. **Conclusion**: Since the sex of the child is determined by the type of sperm (X or Y) contributed by the father, the correct answer to the question is that sex determination in humans takes place by the sex chromosomes of the father.

**Final Answer**: Sex determination in humans takes place by the sex chromosomes of the father.

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