Meiosis in spirogyra/Chlamydomonas/Ulothrix occurs

Options

A. as the zygospore germinates
B. during conjugation
C. during palmella formation
D. during formation of gametes

Answer

**Step-by-Step Solution:**

1. **Identify the Organisms**: The question mentions three organisms: Spirogyra, Chlamydomonas, and Ulothrix. All these organisms are classified as algae.

2. **Understand Reproduction in Algae**: Algae can reproduce through three main methods:
- Vegetative reproduction
- Asexual reproduction
- Sexual reproduction

3. **Focus on Asexual Reproduction**: In algae, asexual reproduction is significant. It typically involves the formation of zoospores, which are a type of asexual spore.

4. **Definition of Zoospores**: Zoospores are motile spores that are produced under favorable conditions. They play a crucial role in the life cycle of algae.

5. **Meiosis Process**: After the formation of zoospores, they undergo zygotic meiosis. This process leads to the formation of new spores, which can be either motile (tetraflagellated) or non-motile (aplanospores).

6. **Haploid Nature of Meospores**: The resulting meospores from meiosis are haploid. Each haploid meospore can germinate to form new filaments, contributing to the growth of algae.

7. **Conclusion**: Therefore, meiosis in Spirogyra, Chlamydomonas, and Ulothrix occurs during the germination of the zygospore, which is formed from the fusion of gametes.

**Final Answer**: Meiosis in Spirogyra, Chlamydomonas, and Ulothrix occurs during the germination of the zygospore.

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