At which stage of meiosis does the genetic constitution of gametes is finally decided?

Options

A. Metaphase I
B. Anaphase II
C. Metahphase II
D. Anaphase I

Answer

To determine at which stage of meiosis the genetic constitution of gametes is finally decided, we can break down the process of meiosis and analyze the key stages involved.

### Step-by-Step Solution:

1. **Understanding Meiosis**:
- Meiosis is a type of cell division that reduces the chromosome number by half, resulting in four haploid gametes from one diploid cell. It consists of two main stages: Meiosis I and Meiosis II.

2. **Meiosis I vs. Meiosis II**:
- In Meiosis I, homologous chromosomes are separated, while in Meiosis II, sister chromatids are separated. The genetic constitution of the gametes is primarily influenced during Meiosis I.

3. **Stages of Meiosis I**:
- Meiosis I includes several stages: Prophase I, Metaphase I, Anaphase I, and Telophase I.
- During Prophase I, homologous chromosomes pair up and exchange genetic material (crossing over).
- In Metaphase I, these homologous pairs align at the equatorial plate.
- Anaphase I is where the homologous chromosomes are pulled apart to opposite poles of the cell.

4. **Key Stage for Genetic Constitution**:
- The genetic constitution of the gametes is finally decided during **Anaphase I**. At this stage, the homologous chromosomes separate, and each daughter cell will receive a different combination of maternal and paternal chromosomes, determining the genetic makeup of the resulting gametes.

5. **Conclusion**:
- Therefore, the stage of meiosis at which the genetic constitution of gametes is finally decided is **Anaphase I**.