Menustration is a result of

Options

A. Disintegration of epimetrium
B. disintegration of endometrium
C. progression of endometrium
D. regression of myometrium

Answer

**Step-by-Step Solution:**

1. **Understanding Menstruation**: Menstruation is a monthly process that occurs in the female reproductive system. It involves the shedding of the uterine lining when fertilization does not take place.

2. **Role of the Endometrium**: The endometrium is the inner lining of the uterus that thickens each month in preparation for a potential pregnancy. If fertilization occurs, the fertilized egg (zygote) will implant itself into the endometrium.

3. **Fertilization Process**: Fertilization is the fusion of the male gamete (sperm) and the female gamete (egg), resulting in the formation of a zygote. This zygote then develops into a blastula, which is essential for implantation.

4. **What Happens if Fertilization Does Not Occur**: If the egg is not fertilized, the body does not need the thickened endometrial lining. Therefore, the endometrium will disintegrate.

5. **Disintegration of the Endometrium**: The disintegration of the endometrium leads to the shedding of its lining, which is what constitutes menstruation. This process involves the release of blood and tissue from the uterus through the vagina.

6. **Conclusion**: Thus, menstruation is a result of the disintegration of the endometrium when no fertilization occurs.

**Final Answer**: Menstruation is a result of the disintegration of the endometrium.

---