A reduction step during meiosis is important because

Options

A. It returns the chromosomes number to normal before fertilization
B. There is a mechanism for this
C. Only one copy of each chromosome is necessary
D. Otherwise chromosome copies would double each fertilization

Answer

**Step-by-Step Solution:**

1. **Understanding Meiosis**: Meiosis is a type of cell division that reduces the chromosome number by half, resulting in the formation of gametes (sperm and egg cells). It consists of two main stages: Meiosis I and Meiosis II.

2. **Reduction of Chromosome Number**: In a diploid (2N) cell, meiosis begins with one cell that contains two sets of chromosomes. During Meiosis I, homologous chromosomes are separated, resulting in two haploid (N) cells. This is the reduction step where the chromosome number is halved.

3. **Formation of Gametes**: After Meiosis I, each haploid cell undergoes Meiosis II, which is similar to mitosis. This results in a total of four haploid gametes from the original diploid cell.

4. **Importance of Reduction Step**: The reduction step is crucial because it ensures that when two gametes (one from each parent) fuse during fertilization, the resulting zygote will have the correct diploid number of chromosomes (2N). Without this reduction, the zygote would have an abnormal number of chromosomes.

5. **Conclusion**: Therefore, the reduction step during meiosis is important because it returns the chromosome number to normal (diploid) before fertilization occurs.

**Final Answer**: A reduction step during meiosis is important because it returns the chromosome number to normal (2N) before fertilization.

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