A population of plants experiences several years of severe drought. Much of the population dies due to lack of water, but a few individuals survive. You set out to discover the physiological basis for their adaptation to such an extreme environmental change. You hypothesize that the survivors have the ability to synthesize higher levels of than their siblings do.

Question

Quizplus · Accepted Answer

ABA (abscisic acid) is a plant hormone that is known to be involved in regulating plant growth and development in response to environmental stress. During periods of drought, ABA levels in plants increase, leading to the closure of stomata and reduced water loss. This allows the plants to conserve water, which can increase their chances of survival in harsh conditions. Therefore, it is likely that the survivors of the drought have the ability to synthesize higher levels of ABA than their siblings do, which could be a key factor in their adaptation to extreme environmental change.

A Population of Plants Experiences Several Years of Severe Drought