Answer: Negative.
- A More positive
- B Remain at zero
- C Negative
- D Become infinite
Correct answer: C. Negative
Explanation: Pure water has a solute potential of zero; dissolving a solute lowers it to a negative value.
Water can travel through cell walls (apoplast) or cell-to-cell through the cytoplasm (symplast) - but the Casparian strip at the endodermis blocks the apoplast route entirely, forcing everything through a selectively permeable membrane (symplast) before it can enter the xylem.
Concept context
Water and mineral absorption, the ascent of sap, transpiration, and phloem transport via the pressure flow hypothesis.