Progesterone

Options

A. Supports the pregnancy
B. Acts on the mammary gland and stimulate the formation of alveoli
C. Both (1) and (2)
D. Controls secondary sexual characters in females

Answer

### Step-by-Step Solution for the Question on Progesterone:

1. **Definition of Progesterone**:
- Progesterone is a steroid hormone primarily secreted in females. It plays a crucial role in the menstrual cycle, pregnancy, and embryogenesis.

2. **Source of Progesterone**:
- In females, progesterone is mainly secreted by the corpus luteum, which forms from the remnants of the Graafian follicle after ovulation.
- Additionally, during pregnancy, progesterone is secreted by the placenta.

3. **Functions of Progesterone**:
- **Supports Pregnancy**: Progesterone prepares the endometrium (the inner lining of the uterus) for the implantation of a fertilized egg and maintains the uterine environment suitable for the developing fetus.
- **Mammary Gland Development**: It stimulates the formation of alveoli in the mammary glands, which are essential for milk production.

4. **Misconceptions**:
- It is important to note that while progesterone plays significant roles in pregnancy and mammary gland development, it does not control secondary sexual characteristics in females. This function is primarily attributed to estrogen.

5. **Conclusion**:
- Based on the functions of progesterone, the correct answer to the question is that progesterone supports pregnancy and acts on the mammary gland to stimulate the formation of alveoli.

### Final Answer:
Progesterone supports pregnancy and stimulates the formation of alveoli in the mammary glands.

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