[Campbell Biology P.838] According to the text, which statement accurately distinguishes bet... | Practice Question

According to the text, which statement accurately distinguishes between solute potential Ψs and pressure potential Ψp in plants?

  • A: Ψs is always a positive number, while Ψp is always negative.
  • B: Ψs relates to the physical pressure on a solution, whereas Ψp is directly proportional to solute molarity.
  • C: An increase in solute concentration makes Ψs more negative, and living cells typically have positive Ψp due to turgor pressure.
  • D: Pure water has a Ψp of 0 MPa, and a 0.1 M sugar solution has a Ψs of +0.23 MPa.

Explanation

The text states that an increase in solute concentration makes Ψs more negative, and provides an example of -0.23 MPa for a 0.1 M sugar solution. It also explains that water in living cells is usually under positive pressure due to osmotic uptake, creating turgor pressure positive Ψp .