water potential

Question 1

water potential (ψ) definition

Answer 1

H2O moves from high ψ 🡪 low ψ potential

Question 2

water potential equation

Answer 2

ψ = ψS + ψP
Water potential (ψ)
Solute potential (ψS)
Pressure potential (ψP)

Question 3

Solute potential (ψS)

Answer 3

solute concentration (osmotic potential)

Question 4

Pressure potential (ψP)

Answer 4

physical pressure on solution; turgor pressure (plants)

Question 5

pressure potential of pure/distilled water

Answer 5

0 MPa

Question 6

pressure potential of plant cells

Answer 6

1 MPa

Question 7

solute potential equation

Answer 7

ψS = -iCRT

i = ionization constant (# particles made in water)
C = molar concentration
R = pressure constant (0.0831 liter bars/mole-K)
T = temperature in K (273 + °C)

Question 8

what effect does the addition of solute to water have on the water potential?

Answer 8

decreases the water potential because it lowers the solute potential

Question 9

where will water move

Answer 9

from an area of:
higher ψ 🡪 lower ψ (more negative ψ)
low solute conc. 🡪 high solute conc.
high pressure 🡪 low pressure