What does the prostate gland secrete and why?

• A. Proteolytic enzymes that break down clotting factors in ejaculate to allow semen to remain in a fluid state
• B. Lipid-based lubricants
• C. Antibiotics
• D. Glycogen

Answer: (A)

The main idea is that prostatic fluid contains proteolytic enzymes that liquefy semen after ejaculation. Semen initially forms a gel-like clot due to proteins such as semenogelin from the seminal vesicles. Prostate-secreted proteases, including PSA (prostate-specific antigen), cleave these proteins, converting the clot into a liquid. This liquefaction releases sperm to swim freely, increasing the chances of fertilization. The other options don’t fit because the prostate does not provide lipid-based lubricants, antibiotics, or glycogen as a specific functional secretion in semen.