Question

(i) The figure alongside is a diagram of a root hair. On the diagram, name the parts labelled 1 to 5.
(ii) What role is played in the uptake of water into the root hair by the parts numbered 1, 2 and 3?
(iii) What would happen if living cells of a plant were planted first in a strong solution of cane sugar and then in water?
Figure

Answer 1

(i) 1 - Cell wall, 2 - Plasma membrane, 3 - Vacuole, 4 - Cytoplasm , 5 - Tonoplast

(ii) The cell wall is fully permeable to water; hence, it allows water to enter the cell.
The plasma membrane is a semi-permeable membrane that allows only water to enter and restricts the entry of salts.
The vacuole has a concentrated cell sap, which allows the uptake of water by root hair via osmosis.

(iii) If living cells of a plant were planted first in a strong solution of cane sugar, they would shrink, because of plasmolysis. They would again become normal if placed in water, because of deplasmolysis.