Relaxin is secreted by -

Options

A. Placenta
B. Corpus luteum (in the later phase of pregnancy)
C. Both a and b
D. Pituitary

Answer

**Step-by-Step Solution:**

1. **Understand the Hormone Relaxin**: Relaxin is a hormone that plays a significant role during pregnancy, particularly in preparing the body for childbirth.

2. **Identify the Source of Relaxin**: Relaxin is primarily secreted by the placenta. The placenta is an organ that develops in the uterus during pregnancy and is responsible for nutrient and gas exchange between the mother and fetus.

3. **Role of the Corpus Luteum**: In addition to the placenta, relaxin can also be secreted by the corpus luteum, especially in the later stages of pregnancy. The corpus luteum is a temporary endocrine structure involved in the menstrual cycle and early pregnancy, primarily producing progesterone.

4. **Conclusion**: Therefore, relaxin is secreted by both the placenta and the corpus luteum during pregnancy. However, it is important to note that it is not secreted by the pituitary gland.

5. **Final Answer**: The correct answer is that relaxin is secreted by both the placenta and the corpus luteum.

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