Trace how hypotonic conditions change water, pressure and solute potential inside a root cell until equal water potential stops net movement in IB Biology HL D2.3.11.
(a) Explain how the pressure potential and solute potential change inside a plant root cell when it is placed into a solution that is more hypotonic than the cell's cytoplasm.
Explain how the pressure potential and solute potential change inside a plant root cell when it is placed into a solution that is more hypotonic than the cell's cytoplasm.
a. (when cell is placed in a hypotonic solution) surrounding/outside (of the root hair cell) is more dilute / has higher water potential
OR
water will enter the root hair cell
OR
water moves from high water potential to low water potential;
b. (positive) pressure potential will increase / become more positive;
c. (negative) solute/osmotic potential will increase / become less negative;
d. water potential inside the cell will increase / become less negative;
e. Ψw=Ψs+Ψp;
f. when cell's water potential equals that of the solution, (net) water movement stops;
For e. allow word equation:
Ψw= water potential
Ψs= solute potential
Ψp= pressure potential
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