What would enhance water uptake by a plant cell?
a. Decreasing the Ψ of the surrounding solution
b. Positive pressure on the surrounding solution
c. The loss of solutes from the cell
d. Increasing the Ψ of the cytoplasm

Verified step by step guidance

1. Understand the concept of water potential (Ψ), which is a measure of the potential energy in water and drives the movement of water. Water moves from areas of higher water potential to areas of lower water potential.
2. Recognize that the water potential of a solution is affected by solute concentration and pressure. The formula for water potential is Ψ = Ψs + Ψp, where Ψs is the solute potential and Ψp is the pressure potential.
3. Consider option a: Decreasing the Ψ of the surrounding solution would mean lowering its water potential, making it more negative. This would enhance water uptake by the plant cell because water would move from the higher water potential inside the cell to the lower water potential outside.
4. Evaluate option b: Positive pressure on the surrounding solution would increase the Ψp, potentially increasing the water potential of the surrounding solution, which might not enhance water uptake as water moves from higher to lower potential.
5. Analyze option c and d: The loss of solutes from the cell (option c) would increase the Ψs inside the cell, potentially reducing water uptake. Increasing the Ψ of the cytoplasm (option d) would make the water potential inside the cell higher, which would not enhance water uptake as water moves from higher to lower potential.

Key Concepts

Water Potential (Ψ)

Water potential (Ψ) is a measure of the potential energy in water, influencing the direction of water movement. It is affected by solute concentration and pressure, with water moving from areas of higher to lower water potential. Understanding Ψ is crucial for determining how water uptake by plant cells is influenced by surrounding conditions.

Osmosis

Osmosis is the passive movement of water across a semipermeable membrane from a region of lower solute concentration to higher solute concentration. In plant cells, osmosis drives water uptake, with water moving into cells when the external environment has a lower water potential than the cell's interior, facilitating nutrient absorption and cell turgor.

Pressure Potential

Pressure potential is a component of water potential that accounts for the physical pressure exerted on water within plant cells. Positive pressure can increase water potential, promoting water movement into cells. Understanding how pressure potential interacts with solute concentration helps explain how external pressures can enhance or inhibit water uptake in plant cells.