A Chlamydomonas plant is left exposed in mud. What would be its means of survival ?

Options

A. Formation of aplanospores
B. Palmella stage
C. Formation of hypnospores
D. All the above.

Answer

To determine the means of survival for a Chlamydomonas plant left exposed in mud, we need to analyze the options provided and understand the characteristics of Chlamydomonas.

### Step-by-Step Solution:

1. **Understanding Chlamydomonas**:
- Chlamydomonas is a unicellular green alga that typically thrives in aquatic environments. It is known for its flagella, which allow it to move in water.

2. **Analyzing the Environment**:
- When exposed to mud, the plant faces a harsh environment with limited water availability. This situation requires a survival strategy.

3. **Evaluating the Options**:
- **Aplanospores**: These are asexual spores that are typically motile and not suitable for survival in dry conditions. They are not the correct answer.
- **Palmella Stage**: This is a survival stage for Chlamydomonas under water scarcity. In this stage, the cells form a gelatinous mass which helps them retain moisture and survive in unfavorable conditions. This is a viable means of survival for Chlamydomonas in mud.
- **Hypnospores**: These are non-motile asexual spores that develop a thick wall. While they are a form of asexual reproduction, they are not specifically adapted for the survival of Chlamydomonas in dry conditions.

4. **Conclusion**:
- Given the analysis, the most appropriate means of survival for Chlamydomonas when exposed to mud is the **Palmella stage**. Therefore, the correct answer is option B.

### Final Answer:
The means of survival for a Chlamydomonas plant left exposed in mud is the **Palmella stage** (Option B).

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