Explanation:

Progesterone-only contraceptives (like mini-pills) are effective as regular contraceptive methods, but not ideal for emergency contraception. The primary reason is:

• They may not consistently inhibit ovulation, especially after intercourse when ovulation may already be imminent or occurring.

• Emergency contraception requires a rapid and reliable suppression of ovulation, which is not guaranteed with standard-dose progesterone-only pills.

Instead, high-dose levonorgestrel (a synthetic progestin) is used as emergency contraception, typically in the form of:

• Levonorgestrel 1.5 mg single dose within 72 hours

This high dose can block or delay ovulation effectively if administered early enough.

Final Answer for Q115:

4. Progesterone may not block follicular development or ovulation.

116. MAPK Activation and Inactivation – Assertion & Reason

Assertion A: Mitogen-activated protein kinases (MAPK) are activated by upstream mitogen-activated protein kinase kinases (MAPKK).
Reason R: The activated MAPK are inactivated by mitogen-activated protein kinase phosphatase.

Correct Answer: 2. Both A and R are true but R is NOT the correct explanation of A

Key Phrase: MAPK activation and inactivation pathway

Explanation:

• MAPK (Mitogen-Activated Protein Kinases) are indeed activated by MAPKK (MAPK Kinases). This is a well-established signal transduction cascade in cell biology.

• After activation, MAPK can be inactivated by MAPK phosphatases (MKPs), which dephosphorylate them.

While both statements are factually correct, the Reason (R) does not explain the mechanism of activation (which is what Assertion A is about). Rather, R describes how MAPKs are inactivated, not how they’re activated.

Final Answer for Q116:

2. Both A and R are true but R is NOT the correct explanation of A

Let me know if you want a visual map of the MAPK signaling pathway or emergency contraceptive options comparison.