Which of the following have negative values for a flaccid cell and partly turgid cell ?

Options

A. Water potential
B. Pressure potential
C. Osmotic potential
D. Both 1 & 3

Answer

To solve the question regarding which potentials have negative values for a flaccid cell and a partly turgid cell, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Flaccid Cells**:
- A flaccid cell is one that has lost water and does not undergo endosmosis (the movement of water into the cell). In this state, the cell is not turgid and does not exert pressure against the cell wall.

2. **Water Potential in Flaccid Cells**:
- Water potential (Ψ) is the potential energy of water in a system compared to pure water. For flaccid cells, since there is no net movement of water into the cell, the water potential is negative. This is due to the osmotic potential being lower than that of pure water.

3. **Osmotic Potential in Flaccid Cells**:
- Osmotic potential (Ψs) is also negative in flaccid cells because it reflects the tendency of water to move into the cell. Since the cell has a lower concentration of solutes compared to the surrounding environment, the osmotic potential is negative.

4. **Understanding Partly Turgid Cells**:
- A partly turgid cell has taken in some water but is not fully turgid. This means that while there is some pressure against the cell wall, it is not at maximum turgidity.

5. **Water Potential in Partly Turgid Cells**:
- In a partly turgid cell, the water potential remains negative. Although the cell has taken in water, the pressure potential is not sufficient to make the water potential positive.

6. **Osmotic Potential in Partly Turgid Cells**:
- The osmotic potential in a partly turgid cell is also negative. The cell is still drawing water from the surrounding environment, which means that the osmotic potential remains negative.

7. **Pressure Potential**:
- Pressure potential (Ψp) in both flaccid and partly turgid cells can vary. In flaccid cells, it is zero, while in partly turgid cells, it is positive but not enough to make the overall water potential positive.

8. **Conclusion**:
- Therefore, both the water potential and osmotic potential have negative values for both flaccid and partly turgid cells. The correct answer is that both water potential and osmotic potential (options 1 and 3) are negative.

### Final Answer:
The correct options are **1 and 3**: Water potential and Osmotic potential have negative values for both flaccid and partly turgid cells.