During favourable conditions, the most common mode of multiplication in Chlamydomonas is by producing

Options

A. Gametes
B. Zoospores
C. Aplanospores
D. Hypnospores.

Answer

**Step-by-Step Solution:**

1. **Understanding Chlamydomonas**: Chlamydomonas is a unicellular green alga that can reproduce both sexually and asexually. It is important to identify the conditions under which it reproduces.

2. **Identifying Favorable Conditions**: During favorable conditions, organisms often reproduce asexually to quickly increase their population. In Chlamydomonas, this typically occurs when environmental conditions are optimal (adequate light, nutrients, and temperature).

3. **Analyzing the Options**:
- **Gametes**: These are reproductive cells that participate in sexual reproduction. In Chlamydomonas, gametes are produced during unfavorable conditions, not favorable ones.
- **Zoospores**: These are motile asexual spores that can swim due to flagella. In Chlamydomonas, under favorable conditions, it reproduces by producing zoospores.
- **Aplanospores**: These are non-motile asexual spores that are formed from the vegetative cells. They are not the primary means of reproduction in Chlamydomonas during favorable conditions.
- **Hypnospores**: These are also non-motile asexual spores that are formed under unfavorable conditions. They are not relevant to the question.

4. **Conclusion**: The most common mode of multiplication in Chlamydomonas during favorable conditions is by producing **zoospores**.

5. **Final Answer**: The correct answer is **zoospores**.

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