Turner' s syndrome is due to

Options

A. Monosomy
B. Bisomy
C. Trisomy
D. Polyploidy

Answer

**Step-by-Step Solution:**

1. **Understanding Turner’s Syndrome**:
- Turner’s syndrome is a genetic condition that affects females. It is characterized by the absence or partial absence of one of the X chromosomes.

2. **Identifying the Genetic Abnormality**:
- In Turner’s syndrome, the typical chromosomal arrangement of females (which is usually XX) is altered to X0, meaning one X chromosome is missing.

3. **Analyzing the Options**:
- The options provided are:
- Monosomy
- Bisomy
- Trisomy
- Polyploidy

4. **Defining Each Option**:
- **Monosomy**: This refers to the presence of only one chromosome from a pair. In the case of Turner’s syndrome, there is one X chromosome instead of two.
- **Bisomy**: This term generally refers to the presence of two chromosomes from a pair, which does not apply to Turner’s syndrome.
- **Trisomy**: This indicates the presence of three chromosomes from a pair, which is not relevant to Turner’s syndrome.
- **Polyploidy**: This refers to having more than two complete sets of chromosomes, which is also not applicable here.

5. **Conclusion**:
- Since Turner’s syndrome is characterized by the absence of one X chromosome, it is classified as monosomy. Therefore, the correct answer is that Turner’s syndrome is due to **monosomy**.

**Final Answer**: Turner’s syndrome is due to **monosomy**.

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