Which is false about visibility of mammalian sperm

Options

A. Sperm is visible for only 24 hours.
B. Sperm viability is determined by its motility
C. Sperms must be concentrated in thick suspension
D. It depends upon pH of medium as sperm is more active in alkaline medium.

Answer

To determine which statement is false about the visibility of mammalian sperm, we need to analyze each option provided:

1. **Option A: Sperm is visible for only 24 hours.**
- This statement suggests that sperm can only survive or remain visible for a short duration of 24 hours. However, research indicates that sperm can remain viable in the female reproductive tract for up to 5 days after ejaculation. Therefore, this statement is false.

2. **Option B: Sperm viability is determined by its mortality.**
- This statement implies that the viability of sperm is assessed based on how many sperm cells die. Viability typically refers to the ability of sperm to survive and fertilize an egg, so this statement is somewhat misleading but not necessarily false.

3. **Option C: Sperm must be concentrated in thick suspension.**
- This statement refers to the fact that sperm is usually ejaculated in a thick suspension to ensure that a sufficient number of sperm reach the egg. This is true, as sperm concentration is important for successful fertilization.

4. **Option D: It depends upon the pH of the medium; sperm is more active in alkaline medium.**
- This statement is accurate. Sperm motility is indeed influenced by the pH of the surrounding medium, and sperm tend to be more active in alkaline conditions, which is favorable in the female reproductive tract.

After analyzing all the options, we conclude that the false statement is:

**Final Answer: Option A - Sperm is visible for only 24 hours.**

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