Answer: ethylene.
- A ethylene
- B auxin
- C cytokinin
- D gibberellin
Correct answer: A. ethylene
Explanation: Ethylene, a gaseous hormone, triggers fruit ripening.
Geometric growth (where both daughter cells keep dividing) produces this classic S-shaped curve: a slow lag phase, a rapid exponential phase, and a levelling-off stationary phase as nutrients or space become limiting - the same fundamental pattern seen in population growth.
Concept context
Phases of plant growth, the five classical plant hormones plus newer ones, photoperiodism, vernalization, and seed dormancy.