If a plant cell has `Psi_(S)` value of -10 bar and `Psi_(P)` value of +5 bar ,its water potential `(Psi_(W))` will be

Options

A. `+5` bar
B. `-5` bar
C. `+15` bar
D. `-50` bar

Answer

To find the water potential (\( \Psi_W \)) of a plant cell, we can use the formula:

\[ \Psi_W = \Psi_S + \Psi_P \]

Where:
- \( \Psi_W \) = Water potential
- \( \Psi_S \) = Solute potential
- \( \Psi_P \) = Pressure potential

### Step-by-Step Solution:

1. **Identify the given values**:
- Solute potential (\( \Psi_S \)) = -10 bar
- Pressure potential (\( \Psi_P \)) = +5 bar

2. **Substitute the values into the formula**:
\[ \Psi_W = \Psi_S + \Psi_P \]
\[ \Psi_W = -10 \, \text{bar} + 5 \, \text{bar} \]

3. **Perform the calculation**:
\[ \Psi_W = -10 + 5 = -5 \, \text{bar} \]

4. **Conclusion**:
The water potential (\( \Psi_W \)) of the plant cell is -5 bar.

### Final Answer:
\[ \Psi_W = -5 \, \text{bar} \]