On germination each zygospore of Spirogyra gives rise to

Options

A. Four plants
B. Three plants
C. Two plants
D. One plant.

Answer

**Step-by-Step Solution:**

1. **Understanding the Zygospore**: The zygospore of Spirogyra is a thick-walled resting cell formed during sexual reproduction. It is produced when two filaments of Spirogyra align and undergo conjugation.

2. **Germination Conditions**: The zygospore remains dormant until favorable conditions for germination arise. This typically involves suitable environmental factors such as temperature and moisture.

3. **Meiotic Division**: Upon germination, the nucleus of the zygospore undergoes meiosis. This process results in the formation of four haploid nuclei.

4. **Disintegration of Nuclei**: Out of the four haploid nuclei produced, three will disintegrate and only one haploid nucleus will remain viable.

5. **Formation of Filament**: The remaining haploid nucleus leads to the bursting of the zygospore's outer wall, resulting in the germination of the zygospore. This process gives rise to one filament.

6. **Conclusion**: Therefore, on germination, each zygospore of Spirogyra gives rise to one filament, which can be considered as one plant.

**Final Answer**: Each zygospore of Spirogyra gives rise to **one plant**.

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