Sleep
Sleep is a naturally recurring state characterized by reduced or absent consciousness, relatively suspended sensory activity, and inactivity of nearly all voluntary muscles. It is distinguished from quiet wakefulness by a decreased ability to react to stimuli, and is more easily reversible than being in hibernation or a coma. Sleep is a heightened anabolic state, accentuating the growth and rejuvenation of the immune, nervous, skeletal and muscular systems. It is observed in all mammals, all birds, and many reptiles, amphibians, and fish.
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Famous quotes containing the word sleep:
“There dwell the children of the dark Night, the dread gods Sleep and Death.”
—Hesiod (c. 8th century B.C.)
“Was it for this the clay grew tall?
MO what made fatuous sunbeams toil
To break earth’s sleep at all?”
—Wilfred Owen (1893–1918)
“Much sleep is not required by nature, either for our souls or bodies, or for the actions in which they are concerned.”
—Plato (c. 427–347 B.C.)