Seeds when placed in water swell because of

Options

A. Osmosis
B. Root pressure
C. Imbibition
D. Diffusion

Answer

**Step-by-Step Solution:**

1. **Understanding the Question:**
- The question asks why seeds swell when placed in water. This involves understanding the processes that occur when seeds come into contact with water.

2. **Analyzing the Options:**
- The options provided are Osmosis, Root Pressure, Imbibition, and Diffusion. We need to evaluate each option to determine which one correctly explains the swelling of seeds.

3. **Evaluating Osmosis:**
- Osmosis is the movement of water from an area of low solute concentration to an area of high solute concentration. While osmosis does involve water movement, it is not the primary reason for the swelling of seeds when they are placed in water.

4. **Evaluating Root Pressure:**
- Root pressure refers to the pressure created in the xylem of plants due to the absorption of ions from the soil. This process is not directly related to the swelling of seeds in water, as it pertains more to water movement within the plant after the roots have absorbed water.

5. **Evaluating Imbibition:**
- Imbibition is a process where water is absorbed by solids or colloids, leading to an increase in their volume. This process is specifically relevant to seeds, as they absorb water and swell due to the imbibition of water.

6. **Evaluating Diffusion:**
- Diffusion is the movement of molecules from an area of higher concentration to an area of lower concentration. While diffusion is important for gas exchange in plants, it does not explain the swelling of seeds in water.

7. **Conclusion:**
- Based on the analysis, the swelling of seeds when placed in water is primarily due to **Imbibition**. This process allows seeds to absorb water and increase in volume, leading to their swelling.

**Final Answer:**
Seeds swell when placed in water because of **Imbibition**.

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