Vasopressin is responsible for

Options

A. Controlling Oogenesis
B. Regulating blood pressure and act on the nephron tubules
C. Regulating formation of pigment
D. Controlling spermatogenesis

Answer

### Step-by-Step Solution:

1. **Identify the Hormone**: The question asks about vasopressin, which is also known as Antidiuretic Hormone (ADH). It is produced in the hypothalamus and released from the posterior pituitary gland.

2. **Understand the Functions of Vasopressin**:
- Vasopressin primarily acts on the kidneys.
- Its main role is to conserve water in the body by stimulating the reabsorption of water in the nephron tubules.

3. **Analyze the Options Given**:
- **Controlling Oogenesis**: Oogenesis is the formation of ova (egg cells) in females. Vasopressin does not play a role in this process.
- **Regulating Blood Pressure**: Vasopressin can constrict blood vessels, which helps in regulating blood pressure. This is one of its key functions.
- **Act on Nephron Tubules**: Vasopressin acts on the nephron tubules to promote water reabsorption, which is a direct action of the hormone.
- **Regulating the Formation of Pigment**: This is not a function of vasopressin.
- **Controlling Spermatogenesis**: Spermatogenesis is the process of sperm formation, which is not influenced by vasopressin.

4. **Select the Correct Answer**: Based on the analysis, the correct functions of vasopressin are:
- Regulating blood pressure.
- Acting on nephron tubules to conserve water.

Thus, the correct answer is that vasopressin is responsible for regulating blood pressure and acting on nephron tubules.

### Final Answer:
Vasopressin is responsible for regulating blood pressure and acting on nephron tubules to conserve water.

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