Cell A, B and C are present in a sequence. The `Psi` values of these cells are -3, -6 and -10 MPa respectively. What is the direction of water flow among the cells ?

Options

A. `AtoBtoC`
B. `BtoAtoC`
C. `CtoBtoA`
D. `AtoCtoB`

Answer

To determine the direction of water flow among the cells A, B, and C based on their water potential (Ψ) values, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Ψ Values**:
- Cell A: Ψ_A = -3 MPa
- Cell B: Ψ_B = -6 MPa
- Cell C: Ψ_C = -10 MPa

2. **Understand Water Potential**:
- Water moves from areas of higher water potential to areas of lower water potential. In terms of Ψ values, this means that water will flow from a less negative value to a more negative value.

3. **Compare the Ψ Values**:
- We can compare the Ψ values:
- Ψ_A (-3 MPa) is greater than Ψ_B (-6 MPa)
- Ψ_B (-6 MPa) is greater than Ψ_C (-10 MPa)

4. **Determine the Flow Direction**:
- Since water flows from higher potential (less negative) to lower potential (more negative), the flow will be:
- From Cell A (Ψ_A = -3 MPa) to Cell B (Ψ_B = -6 MPa)
- Then from Cell B (Ψ_B = -6 MPa) to Cell C (Ψ_C = -10 MPa)

5. **Conclusion**:
- Therefore, the direction of water flow among the cells is from Cell A to Cell B to Cell C.

### Final Answer:
The correct option is **1: A to B to C**.

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