Meiosis in Spirogyra occurs at the time of

Options

A. Zoospore formation
B. Gametes formation
C. Akinete formation
D. Germination of zygospore.

Answer

### 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 cells from one diploid cell. This process is crucial for sexual reproduction and occurs in organisms that reproduce sexually.

2. **Identifying Spirogyra**: Spirogyra is a genus of green algae belonging to the phylum Chlorophyta. It is primarily photosynthetic and has a life cycle that is predominantly haploid.

3. **Life Cycle of Spirogyra**: The life cycle of Spirogyra is classified as haplontic, meaning that the dominant phase is haploid (N). The only diploid stage occurs after fertilization.

4. **Formation of Zygospores**: When two haploid gametes fuse during fertilization, they form a diploid zygote, which develops into a zygospore. This zygospore is the only diploid structure in the life cycle of Spirogyra.

5. **Germination of Zygospores**: The zygospore undergoes meiosis when it germinates. During this process, the diploid zygospore divides meiotically to produce haploid cells, which will develop into new Spirogyra filaments.

6. **Conclusion**: Therefore, meiosis in Spirogyra occurs at the time of the germination of zygospores. This is the key point in the life cycle where the diploid number is reduced back to haploid.

### Final Answer:
Meiosis in Spirogyra occurs at the time of **germination of zygospores**.

---