Answer: Promotes stomatal closure and dormancy in response to water stress.
- A Promotes stomatal closure and dormancy in response to water stress
- B Stimulates seed germination under high humidity conditions
- C Promotes flowering specifically in response to cold temperatures
- D Promotes rapid cell elongation under conditions of high water availability
Correct answer: A. Promotes stomatal closure and dormancy in response to water stress
Explanation: Abscisic acid accumulates under water stress and other unfavourable conditions, promoting stomatal closure to reduce water loss and inducing seed and bud dormancy.
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.