In the process of osmosis in the cell

Options

A. Both cell wall and protoplasm will act as a membrane
B. Entire protoplast act as a membrane
C. An only outermost layer of protoplasm act as a membrane
D. Only cell wall act as a membrane

Explanation

### Step-by-Step Solution:

1. **Understanding Osmosis**:
- Osmosis is the movement of water molecules through a semi-permeable membrane from an area of low solute concentration to an area of high solute concentration until equilibrium is reached.

2. **Identifying the Membrane in Cells**:
- In plant cells, the outermost layer is the cell wall, but the key functional barrier for osmosis is the plasma membrane (also known as the cell membrane). The plasma membrane is selectively permeable, allowing certain substances to pass while blocking others.

3. **Role of the Plasma Membrane**:
- The plasma membrane regulates the entry and exit of water and solutes. It is crucial for maintaining the cell's internal environment, which is essential for osmosis to occur effectively.

4. **Direction of Water Movement**:
- During osmosis, water moves from a region of higher water concentration (or lower solute concentration) to a region of lower water concentration (or higher solute concentration). This movement is driven by the concentration gradient.

5. **Conclusion**:
- In the context of the question, when considering the process of osmosis in a cell, the outermost layer of protoplasm (which is the plasma membrane) acts as the membrane through which osmosis occurs. Therefore, the correct answer is that the outermost layer of protoplasm acts as a membrane.

### Final Answer:
In the process of osmosis in the cell, the outermost layer of protoplasm (the plasma membrane) acts as a semi-permeable membrane.

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