Correct the statements

a. Cells shrink in hypotonic solutions and swell in hypertonic solutions.


b. Imbibition is a special type of diffusion when water is absorbed by living cells.


c. Most of the water flow in the roots occurs via the symplast.



a) Cells shrink in hypertonic solution and swell in hypotonic solutions.

Explanation: A hypertonic solution has more concentration of solution thus the net movement of water is from the cell to the outside causing the cell to shrink as water moves out of the cell. A hypotonic solution has less solute concentration as compared to within the cell so there is a net movement of water inside the cell from outside causing the cell to swell.


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b) Imbibition is a special type of diffusion when water is absorbed by dead or living cells.


Explanation: Imbibition is a special type of diffusion when water is absorbed by dead or living cells. Eg: absorption of water by seeds which is required for germination or absorption of water by dry wood that causes it to swell.


c) Most of the water flow in roots occur via the apoplast pathway.


Explanation:


In the symplast pathway, water moves between cytoplasm or vacuoles of the neighbouring cells. In the apoplast pathway can only take water near the xylem, where the Casparian strip forms an impermeable barrier to water in the cell walls, so water moves into the cytoplasm.


Water flows in the root via the apoplast pathway as the cortical cells are loosely packed and hence offers no resistance to movement of water. This mass flow of water occurs due to adhesion and cohesion properties of water.


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