The notion that sleep or wakefulness is regulated by a substance that circulates within the blood is
A) proven by the observation that naps reduce sleep time the following night.
B) unlikely, given that the cerebral hemispheres of a dolphin sleep at different times.
C) REM and slow-wave sleep appear to involve independent mechanisms.
D) proven by studies of the dolphin sleep cycle.
E)proven by studies in which blood transfusion from a tired person to a rested person results in sleep in the recipient.

Question

Quizplus · Accepted Answer

The fact that the cerebral hemispheres of a dolphin sleep at different times suggests that sleep regulation is not solely dependent on a circulating substance in the blood, as this would likely affect both hemispheres simultaneously.

The Notion That Sleep or Wakefulness Is Regulated by a Substance