Which of the following is not a significance of meiosis ?

Options

A. Frormation of gametes
B. Increases genetic variability
C. Reduction of chromosome number of half
D. Replaces old dead and worn out cells

Answer

To determine which of the following is not a significance of meiosis, we need to analyze the options provided. Meiosis is a type of cell division that reduces the chromosome number by half, resulting in the formation of gametes (sperm and eggs). It has several significant roles in biological processes.

### Step-by-Step Solution:

1. **Understand Meiosis**: Meiosis is a reduction division that occurs in sexually reproducing organisms. It reduces the chromosome number from diploid (2N) to haploid (N), resulting in gametes.

2. **Identify the Significance of Meiosis**:
- **Gamete Formation**: Meiosis is essential for the formation of gametes, which are necessary for sexual reproduction. This is a significant role of meiosis.
- **Genetic Variability**: Meiosis introduces genetic variation through processes like crossing over and independent assortment. This increases the genetic diversity of offspring, which is another key significance of meiosis.
- **Reduction of Chromosome Number**: The primary function of meiosis is to reduce the chromosome number by half, ensuring that when fertilization occurs, the resulting zygote has the correct diploid number of chromosomes.

3. **Evaluate the Options**:
- If one of the options states that meiosis replaces old and worn-out cells, we need to analyze this claim.
- Meiosis does not replace old or dead cells; instead, it produces gametes that are used for reproduction. The replacement of old and worn-out cells typically occurs through mitosis, not meiosis.

4. **Conclusion**: Based on the analysis, the option that states "replaces the old and dead worn-out cells" is not a significance of meiosis. Therefore, this option is the correct answer to the question.

### Final Answer:
The option that is not a significance of meiosis is: **Replaces the old and dead worn-out cells**.

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