Resurrection plants of Selaginella and lichens remain air dry for considerable periods because they can absorb water from the slight downpour. By which physiological process water is absorbed

Options

A. active absorption
B. plasmolysis
C. Imbibition
D. osmosis

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the physiological process through which resurrection plants like Selaginella and lichens can absorb water from light downpours after being air-dried for extended periods.

2. **Defining Resurrection Plants and Lichens**: Resurrection plants, such as Selaginella, and lichens are known for their ability to survive extreme dehydration. They can enter a dormant state and revive when water becomes available.

3. **Identifying the Options**: The options provided include:
- Active absorption
- Plasmolysis
- Imbibation
- Osmosis

4. **Analyzing Each Option**:
- **Active Absorption**: This process requires energy to move substances against a concentration gradient, which is not the case for the absorption of water in these plants.
- **Plasmolysis**: This refers to the shrinkage of the cell membrane away from the cell wall due to loss of water in a hypertonic solution. It is not a process of absorption.
- **Imbibation**: This is a special type of diffusion where water is absorbed by solid colloids, leading to an increase in volume. This process is relevant to the absorption of water by resurrection plants and lichens.
- **Osmosis**: This is the movement of water from an area of high concentration to an area of low concentration through a semi-permeable membrane. While osmosis is important in many plant processes, it is not the primary mechanism for the absorption of water in the context of resurrection plants.

5. **Conclusion**: The correct physiological process through which resurrection plants and lichens absorb water from slight downpours is **imbibation**.

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