Pressure potential of a plant cell and its turgor pressure are

Options

A. Numerically equal but first is in negative and second in positive value
B. Numerically equal and both positive
C. Numerically equal but first is positive and second negative
D. Both are numerically different and are negative

Answer

To understand the relationship between pressure potential and turgor pressure in a plant cell, let's break down the concepts step by step.

### Step-by-Step Solution:

1. **Definition of Pressure Potential**:
- Pressure potential (Ψp) is the physical pressure exerted by the fluid (water) inside the plant cell against the cell wall. It is a component of the overall water potential of the cell.

2. **Definition of Turgor Pressure**:
- Turgor pressure is the pressure exerted by the fluid (water) inside the vacuole of a plant cell against the cell wall. It is responsible for maintaining the cell's shape and rigidity.

3. **Mechanism of Water Absorption**:
- When root hairs absorb water from the soil, this water enters the plant cells, increasing the volume of the vacuole. As the vacuole fills with water, it pushes against the cell wall.

4. **Relationship Between Pressure Potential and Turgor Pressure**:
- As water enters the cell and the vacuole expands, both pressure potential and turgor pressure increase. In a healthy, turgid plant cell, the pressure potential is equal to the turgor pressure.

5. **Nature of Values**:
- Both pressure potential and turgor pressure are typically positive values in living plant cells. This means that when we measure these pressures, they will have positive numerical values.

6. **Conclusion**:
- Therefore, we conclude that in a plant cell, the pressure potential and turgor pressure are numerically equal and both are positive.

### Final Answer:
Pressure potential of a plant cell and its turgor pressure are numerically equal and both are positive.

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