A Population of Plants Experiences Several Years of Severe Drought

question 48

Multiple Choice

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.

• A) auxin
• B) gibberellin
• C) cytokinin
• D) abscisic acid

---

Definitions:

Limbic System

An intricate network of nerves and pathways in the brain that regulates instinct and emotional state, governing fundamental emotions like fear, pleasure, and anger as well as primal impulses such as the need for food, sexual activity, domination, and nurturing offspring.

Forebrain

The anterior part of the brain, including the cerebral hemispheres, the thalamus, and the hypothalamus, responsible for a variety of functions including cognition, sensory processing, and motor responses.

Neocortex

The most evolved part of the cerebral cortex that involves higher functions such as sensory perception, generation of motor commands, spatial reasoning, conscious thought, and in humans, language.

Gray Matter

The darker part of the brain and spinal cord consisting mainly of neuronal cell bodies, dendrites, and unmyelinated axons, and is involved in processing information.