Which of the following statements is / are correct regarding the composition of human semen / sperms?
I. The life span of sperms in female genital tract is just 24 hours.
II. Seminal vesicle contribute 20% of the total volume of semen.
III. Survival of sperms depends on the pH of semen, they are killed in acidic medium.
IV. Human sperms move at the rate of 3 mm/s through the female genital tract.

Options

A. I and II only
B. Ill only
C. IV only
D. III and IV only

Answer

To determine which statements regarding the composition of human semen/sperms are correct, we will analyze each statement one by one.

### Step-by-Step Solution:

1. **Statement I**: "The life span of sperms in female genital tract is just 24 hours."
- **Analysis**: This statement is incorrect. The lifespan of sperm in the female reproductive tract is approximately 3 to 5 days, not just 24 hours.
- **Conclusion**: Statement I is **incorrect**.

2. **Statement II**: "Seminal vesicle contributes 20% of the total volume of semen."
- **Analysis**: This statement is also incorrect. The seminal vesicles actually contribute about 70% of the total volume of semen, not 20%.
- **Conclusion**: Statement II is **incorrect**.

3. **Statement III**: "Survival of sperms depends on the pH of semen; they are killed in acidic medium."
- **Analysis**: This statement is correct. Sperm survival is indeed dependent on the pH of the environment. Sperm thrive in an alkaline pH, and they are adversely affected and can be killed in acidic conditions.
- **Conclusion**: Statement III is **correct**.

4. **Statement IV**: "Human sperms move at the rate of 3 mm/s through the female genital tract."
- **Analysis**: This statement is incorrect. The average speed of sperm movement in the female genital tract is approximately 5 mm/s, not 3 mm/s.
- **Conclusion**: Statement IV is **incorrect**.

### Final Conclusion:
Only **Statement III** is correct. Therefore, the correct answer is that only the third statement is true regarding the composition of human semen/sperms.

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