Select the hormone which increases RBC count and decreases WBC (Eosinophil) count

Options

A. Thyroxine
B. Erythropoietin
C. Cortisol
D. Growth hormone

Answer

To solve the question of which hormone increases red blood cell (RBC) count and decreases white blood cell (WBC) count (specifically eosinophils), we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Question**: We need to identify a hormone that has the specific function of increasing RBC count while decreasing the count of eosinophils, a type of white blood cell.

2. **Analyzing the Options**:
- **Option 1: Thyroxine**: This hormone is produced by the thyroid gland and primarily regulates metabolism, heart rate, and muscle function. It does not specifically increase RBC count or decrease WBC count.
- **Option 2: Erythropoietin**: This hormone is produced mainly by the kidneys and is known for stimulating the production of red blood cells in the bone marrow. It is also associated with decreasing the production of certain white blood cells, including eosinophils.
- **Option 3: Cortisol**: Known as the stress hormone, cortisol primarily helps in regulating metabolism and the immune response. It can influence WBC counts but does not specifically increase RBC count.
- **Option 4: Growth Hormone**: This hormone is involved in growth and metabolism but does not play a significant role in the regulation of RBC or WBC counts.

3. **Identifying the Correct Answer**: Based on the functions of the hormones analyzed, erythropoietin (Option 2) is the hormone that increases RBC count and decreases eosinophil count.

4. **Conclusion**: The correct answer is **Erythropoietin**.

### Final Answer:
**Erythropoietin** is the hormone that increases RBC count and decreases eosinophil count.

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