Which of the following determines the diffusion of water from one cell to another?
(a) Diffusion pressure deficit
(b) Hydrostatic pressure
(c) Osmotic pressure
(d) Wall pressure

Options

A. Diffusion pressure deficit
B. Hydrostatic pressure
C. Osmotic pressure
D. Wall pressure

Answer

To determine which of the following options influences the diffusion of water from one cell to another, we need to analyze each option provided:

1. **Diffusion Pressure Deficit (DPD)**:
- DPD refers to the difference in water potential between two solutions. It is the driving force for the movement of water from one cell to another. Water moves from an area of higher water potential (lower DPD) to an area of lower water potential (higher DPD). Therefore, DPD is a key factor that determines the diffusion of water between cells.

2. **Hydrostatic Pressure**:
- Hydrostatic pressure is the pressure exerted by a fluid at equilibrium due to the force of gravity. While it can influence the movement of water in certain contexts (like in xylem transport), it does not directly determine the diffusion of water between cells.

3. **Osmotic Pressure**:
- Osmotic pressure is the pressure required to prevent the flow of water across a semipermeable membrane due to osmosis. While it is related to the movement of water, it does not directly dictate the diffusion of water from one cell to another in the same way that DPD does.

4. **Wall Pressure**:
- Wall pressure is the pressure exerted by the cell wall against the cell's internal pressure. It is more relevant to the structural integrity of the cell and does not influence the diffusion of water between cells.

Based on this analysis, the correct answer is:

**(a) Diffusion pressure deficit**

### Step-by-Step Solution:
1. **Identify the question**: We need to find out which factor determines the diffusion of water between cells.
2. **Analyze each option**:
- DPD is the difference in water potential that drives water movement.
- Hydrostatic pressure relates to fluid pressure but does not directly influence cell-to-cell water diffusion.
- Osmotic pressure is related to solute concentration but not directly to diffusion between cells.
- Wall pressure pertains to structural aspects of cells and does not affect water diffusion.
3. **Conclude**: The factor that directly determines the diffusion of water from one cell to another is the diffusion pressure deficit (DPD).