Question

Correct equation of water potential of a cell:

• A. \( \Psi_w = \Psi_p + \Psi_{mp} \)
• B. \( \Psi_w = \Psi_s - \Psi_p \)
• C. \( \Psi_w = \Psi_s + \Psi_p \)
• D. \( \Psi_w = \Psi_s + \Psi_{mp} \)

Hint:

Remember, water potential and its components are crucial in understanding how water moves in plants through osmosis.

Answer 1

The Correct Option is C

Water potential (\( \Psi_w \)) is calculated as the sum of solute potential (\( \Psi_s \)) and pressure potential (\( \Psi_p \)), which reflects the formula: \[ \Psi_w = \Psi_s + \Psi_p. \] This is confirmed as the correct equation because it integrates both the solute concentration and the physical pressure within the cell.

Answer 2

To solve the problem, we need to identify the correct equation for the water potential of a cell.

1. Understanding Water Potential:
Water potential ($\Psi_w$) is the potential energy of water in a system and is used to predict the direction of water movement. The equation for the water potential of a cell is a combination of different components:

• Solute potential ($\Psi_s$): It is the potential due to the presence of solutes.
• Pressure potential ($\Psi_p$): It is the potential due to the pressure exerted by the cell wall.
• Matric potential ($\Psi_{mp}$): It is the potential due to the interaction of water with solid surfaces like cell walls.

2. The Correct Equation:
For a cell, the water potential is the sum of the solute potential and the pressure potential, as matric potential is generally not considered in the basic equation of water potential for a plant cell.
Thus, the correct equation is:

Final Answer:
The correct option is (C) $\Psi_w = \Psi_s + \Psi_p$.