Which of the following stimulates protein metabolism and muscle growth

Options

A. Estrogen
B. Testosterone
C. Porgesterone
D. Oxytocin.

Answer

To solve the question "Which of the following stimulates protein metabolism and muscle growth?" we will analyze each of the given options: estrogen, testosterone, progesterone, and oxytocin.

### Step-by-Step Solution:

1. **Identify the Hormones**: The options provided are:
- Estrogen
- Testosterone
- Progesterone
- Oxytocin

2. **Analyze Estrogen**:
- Estrogen is primarily known as the main female hormone.
- Its main functions include regulating the growth of the ovaries and controlling female reproductive functions.
- **Conclusion**: Estrogen does not stimulate protein metabolism or muscle growth.

3. **Analyze Testosterone**:
- Testosterone is the main male hormone.
- It is responsible for various functions, including the growth of male sex organs and secondary sexual characteristics (like body hair).
- Importantly, testosterone stimulates protein metabolism and promotes muscle growth.
- **Conclusion**: Testosterone is a key hormone for protein metabolism and muscle growth.

4. **Analyze Progesterone**:
- Progesterone is primarily involved in regulating the menstrual cycle and maintaining pregnancy.
- It helps in the development of the corpus luteum and lactating glands.
- **Conclusion**: Progesterone does not stimulate protein metabolism or muscle growth.

5. **Analyze Oxytocin**:
- Oxytocin is released from the posterior pituitary gland.
- Its primary role is to stimulate uterine contractions during childbirth and to aid in milk ejection during breastfeeding.
- **Conclusion**: Oxytocin does not stimulate protein metabolism or muscle growth.

6. **Final Conclusion**:
- Among the options provided, **testosterone** is the hormone that stimulates protein metabolism and muscle growth.

### Answer:
**Testosterone** stimulates protein metabolism and muscle growth.

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