Which of the following process requires membrane proteins ?

Options

A. Simple diffusion
B. Imbibition
C. Facilitated diffusion
D. More than one option is correct

Answer

To solve the question "Which of the following processes requires membrane proteins?" we will analyze the options provided: simple diffusion, imbibation, facilitated diffusion, and more than one option is correct.

### Step-by-Step Solution:

1. **Understanding Simple Diffusion**:
- Simple diffusion is the movement of molecules from an area of high concentration to an area of low concentration without the need for energy or assistance from membrane proteins.
- **Conclusion**: Simple diffusion does not require membrane proteins.

2. **Understanding Imbibation**:
- Imbibation is the process of absorption of water by solids, particularly colloids, leading to an increase in volume. This process also occurs without the need for membrane proteins.
- **Conclusion**: Imbibation does not require membrane proteins.

3. **Understanding Facilitated Diffusion**:
- Facilitated diffusion is a type of passive transport that also moves substances from high concentration to low concentration. However, it requires the assistance of membrane proteins (such as channel proteins or carrier proteins) to help transport specific molecules across the membrane.
- **Conclusion**: Facilitated diffusion requires membrane proteins.

4. **Evaluating the Options**:
- Based on the analysis:
- Simple diffusion: No membrane proteins required.
- Imbibation: No membrane proteins required.
- Facilitated diffusion: Membrane proteins required.
- More than one option is correct: This is not applicable since only facilitated diffusion requires membrane proteins.

5. **Final Answer**:
- The correct answer is **facilitated diffusion**.