Turner's syndorme is

Options

A. Case of monosomy
B. Cause of sterility in females
C. Absence of Barr body
D. All the above

Answer

**Step-by-Step Solution:**

1. **Understanding Turner's Syndrome**: Turner's syndrome is a genetic condition that affects females, characterized by the absence of one of the two X chromosomes. This results in a chromosomal pattern of 45 chromosomes instead of the typical 46, leading to the designation of the genotype as XO.

2. **Identifying Monosomy**: The term "monosomy" refers to the presence of only one chromosome from a pair. In the case of Turner's syndrome, there is a missing X chromosome, making it a classic example of monosomy.

3. **Effects on Female Sterility**: Due to the absence of one X chromosome, females with Turner's syndrome often experience underdeveloped sexual characteristics and may face infertility. The lack of proper hormonal development due to the missing chromosome contributes to this sterility.

4. **Absence of Barr Body**: Normally, in females with two X chromosomes, one X chromosome condenses into a structure known as the Barr body. However, in Turner's syndrome, since there is only one X chromosome, there is no Barr body present.

5. **Conclusion**: Given that Turner's syndrome is a case of monosomy, causes sterility in females, and is characterized by the absence of Barr bodies, the correct answer is "all of the above."

**Final Answer**: All of the above.

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