What shall be the water potential of a root hair cell absorbing water from the soil

Options

A. Zero
B. Less than zero
C. More than zero
D. Infinite

Answer

To determine the water potential of a root hair cell absorbing water from the soil, we can follow these steps:

### Step 1: Understand Water Potential
Water potential (Ψ) is defined as the potential energy of water in a system compared to pure water. It is a measure of the tendency of water to move from one area to another and is influenced by solute concentration and pressure.

### Step 2: Identify the Value of Pure Water
Pure water has a water potential of 0. This is the highest value for water potential because it contains no solutes. In any solution, the presence of solutes will lower the water potential.

### Step 3: Consider the Root Hair Cell
A root hair cell absorbs water from the soil. The water in the soil is not pure; it contains various nutrients and minerals, which means it has solutes dissolved in it.

### Step 4: Determine the Water Potential of the Solution
Since the water in the soil contains solutes, the water potential of this solution will be negative. The presence of solutes decreases the water potential, making it less than zero.

### Step 5: Conclusion
Therefore, the water potential of the root hair cell, which is absorbing this solute-rich water, will also be less than zero. It can be measured to be in the range of -1 to -4 atmospheric pressure, indicating a negative value.

### Final Answer
The water potential of a root hair cell absorbing water from the soil is **less than 0**.

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