Question

Select the correct option.

Assertion (A): A plant cell does not burst when placed in a hypotonic condition.

Reason (R): Cell wall withstands the internal pressure of the swollen cell.

• A. Both (A) and (R) are correct
• B. Both (A) and (R) are incorrect
• C. (A) is correct and (R) is incorrect
• D. (A) is incorrect and (R) is correct

Answer 1

The correct option is A Both (A) and (R) are correct

$\bullet$ Plant cells are enclosed by a rigid cell wall. When the plant cell is placed in a hypotonic solution, it takes up water by osmosis and starts to swell, but the cell wall prevents it from bursting.
$\bullet$ Turgor pressure is the force exerted by the fluids within the cell. It pushes the plasma membrane against the cell wall.
$\bullet$ The cell wall in turn exerts a force on the fluids within the cell and this is called the wall pressure.
$\bullet$ So, both the turgor pressure and wall pressure work to neutralize each other.
$\bullet$ Animal cells do not have cell walls so, in hypotonic solutions, animal cells swell up and explode.