(a) Solution S is hypotonic to cell sap of potato cylinder cells; the cells drew in water by osmosis increased in size and became turgid hence increase in length and stiffness in cylinder.
Solution T was hypertonic to cells of potato cylinder; the cells lost water by osmosis to solution
T and became flaccid leading to decrease in length and becoming flexible.
(b) Active transport refers to movement of molecules or ions (across a semi-permeable membrane) against the concentration gradient with use of energy, diffusion is the movement of molecules or ions from region of high concentration to region of low concentration.
sharon kalunda answered the question on March 21, 2019 at 14:32
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