Identify the correct statement from the following.

Options

A. High levels of estrogen triggers the ovulatory surge.
B. Oogonial cells start to profiferate and give rise to functional ova in regular cycles from puberty onwards.
C. Sperms released from seminiferous tubules are highly motile.
D. Progesterone level is high during the post-ovulatory phase of menstrual cycle.

Answer

To identify the correct statement from the given options regarding human reproduction, we can analyze each statement step by step:

1. **Statement A**: "High levels of estrogen trigger ovulatory surge."
- Analysis: Ovulation is primarily triggered by a surge in Luteinizing Hormone (LH), not estrogen. While estrogen levels do rise before ovulation, it is the LH surge that directly causes ovulation.
- Conclusion: This statement is **incorrect**.

2. **Statement B**: "Oogenesis starts at puberty."
- Analysis: Oogenesis actually begins before birth in females. The primary oocytes are formed during fetal development and remain in a dormant state until puberty, when they resume development.
- Conclusion: This statement is **incorrect**.

3. **Statement C**: "Sperm released from seminiferous tubules are highly motile."
- Analysis: Sperm are produced in the seminiferous tubules but are not motile until they undergo maturation in the epididymis and receive secretions from accessory glands (like the prostate and seminal vesicles) to form semen.
- Conclusion: This statement is **incorrect**.

4. **Statement D**: "Progesterone level is high during the post-ovulatory phase of the menstrual cycle."
- Analysis: The post-ovulatory phase, also known as the luteal phase, is characterized by high levels of progesterone produced by the corpus luteum. This hormone is crucial for preparing the endometrium for potential implantation of a fertilized egg.
- Conclusion: This statement is **correct**.

Final Answer: The correct statement is **D**: "Progesterone level is high during the post-ovulatory phase of the menstrual cycle."