The Notion That Sleep or Wakefulness Is Produced by a Substance

question 113

Multiple Choice

The notion that sleep or wakefulness is produced by a substance that circulates within the blood is

• A) proven by studies of the dolphin sleep cycle.
• B) unlikely given that the cerebral hemispheres of a dolphin sleep at different times.
• C) unlikely because REM and slow-wave sleep appear to involve independent mechanisms.
• D) proven by the observation that naps reduce sleep time the following night.
• E) unlikely given that blood chemistry does not change within the brain.

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Definitions:

Adrenocorticotrophic Hormone

A hormone produced by the anterior pituitary gland that stimulates the adrenal cortex to secrete cortisol and other hormones.

Adrenal Cortex

The outer portion of the adrenal gland responsible for producing steroid hormones, including cortisol and aldosterone, which regulate metabolism and stress.

Acetylcholine

A neurotransmitter involved in many functions including muscle movement, heart rate, memory, and learning.

Muscle Contractions

The process whereby muscle fibers shorten or lengthen to produce movement or maintain posture as a response to stimulation by nerve impulses.