Choose the correct answer from each of the four options given below:
A plant cell may burst when:
Topic: Turgor pressure and wall pressure
Try it
Pick an option and check your answer. The full worked answer is below either way.
Answer
(b) Turgor pressure exceeds wall pressure.
A cell bursts only when the outward push from inside OVERCOMES the inward resistance of the wall — that is, when TURGOR PRESSURE EXCEEDS WALL PRESSURE.
The two pressures: TURGOR PRESSURE — exerted OUTWARDS by the cell contents against the wall WALL PRESSURE — exerted INWARDS by the rigid wall against the contents
Option (a) describes the NORMAL turgid state: the two are EQUAL and OPPOSITE, the cell is in equilibrium, and nothing further happens. That balance is precisely why a plant cell can sit in pure water WITHOUT bursting, while an animal cell, having no wall, would swell and burst.
In practice a plant cell almost never bursts for this reason — the cellulose wall is strong enough to contain the pressure — which is why the question says "may".
Turgor pressure exceeds wall pressure.