Which hormone is concerned with the concentration of urine :

Options

A. Oxytocin
B. Vassopressin
C. Prolactin
D. Cortisol

Answer

To solve the question regarding which hormone is concerned with the concentration of urine, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Urine Concentration**:
- Concentrated urine means that the solute (like urea, salts) is present in a higher amount compared to the solvent (water). The body regulates this concentration based on hydration levels.

2. **Identifying Relevant Hormones**:
- We need to consider hormones that influence kidney function and water reabsorption. The main hormones to consider are:
- Oxytocin
- Vasopressin (also known as Antidiuretic Hormone, ADH)
- Prolactin
- Cortisol

3. **Analyzing Each Hormone**:
- **Oxytocin**: Released by the posterior pituitary gland, primarily involved in childbirth and lactation. It does not play a role in urine concentration.
- **Vasopressin (Antidiuretic Hormone)**: Released by the posterior pituitary gland, it regulates water reabsorption in the kidneys, specifically in the collecting ducts. This hormone increases water reabsorption, leading to more concentrated urine.
- **Prolactin**: Released by the anterior pituitary gland, it is mainly involved in milk production and does not affect urine concentration.
- **Cortisol**: Released by the adrenal glands, it is involved in metabolism and stress response but does not directly regulate urine concentration.

4. **Conclusion**:
- Based on the functions of the hormones analyzed, the hormone that is primarily responsible for the concentration of urine is **Vasopressin (Antidiuretic Hormone)**.

### Final Answer:
The hormone concerned with the concentration of urine is **Vasopressin (Antidiuretic Hormone)**.

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