University of Central Florida (UCF) BOT3015 Principles of Plant Science Practice Exam 1

Abscisic acid plays a critical role in regulating seed dormancy in plants. This hormone is most well-known for its function in signaling the plant to enter a state of dormancy, which helps seeds survive adverse environmental conditions until they are favorable for germination. During seed development and maturation, abscisic acid levels rise, promoting dormancy and inhibiting germination. It achieves this by enhancing the expression of genes that suppress germination and by affecting physiological processes that maintain seed viability during stress.

In addition to its role in dormancy, abscisic acid is also involved in the plant's response to drought stress, triggering closure of stomata, which helps to conserve water. By helping seeds to remain dormant until conditions are right, abscisic acid ensures that the next generation of plants has a better chance of survival. This adaptation is crucial for plants in fluctuating environmental conditions, making abscisic acid indispensable for seed dormancy regulation.