Bacteria, fungi and lower plants survive during adverse conditions by

Options

A. Suspended growth
B. Migration
C. Diapause
D. Formation of thick-walled spores.

Answer

**Step-by-Step Solution:**

1. **Understanding the Organisms**: Recognize that the question pertains to bacteria, fungi, and lower plants. These organisms are known for their ability to survive in harsh conditions.

2. **Identifying Survival Mechanisms**: Consider the various strategies that these organisms might use to endure adverse environments. The options given are:
- a. Suspended growth
- b. Migration
- c. Diapause
- d. Formation of thick-walled spores

3. **Evaluating Each Option**:
- **Suspended Growth**: This refers to a state where growth is temporarily halted. While some organisms can enter a dormant state, it is not the primary method for bacteria, fungi, and lower plants.
- **Migration**: This involves moving from one place to another to find more favorable conditions. However, bacteria, fungi, and lower plants typically do not migrate.
- **Diapause**: This is a period of suspended development, often seen in certain animals and insects, but not commonly associated with bacteria, fungi, and lower plants.
- **Formation of Thick-Walled Spores**: This is a well-known survival strategy for these organisms. They produce spores that have thick walls, allowing them to withstand extreme conditions such as drought, heat, and lack of nutrients.

4. **Conclusion**: Based on the evaluation, the most effective survival mechanism for bacteria, fungi, and lower plants during adverse conditions is the formation of thick-walled spores.

5. **Final Answer**: The correct answer is option D: Formation of thick-walled spores.

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