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.

Famous quotes containing the word sleep:

““What care I for a goose-feather bed,
With the sheet turned down so bravely, O?
For to-night I shall sleep in a cold open field,
Along with the wraggle taggle gipsies, O!””
—Unknown. The Wraggle Taggle Gipsies (l. 33–36)

“Let me have men about me that are fat,
Sleek-headed men, and such as sleep a-nights.
Yon Cassius has a lean and hungry look;
He thinks too much. Such men are dangerous.”
—William Shakespeare (1564–1616)

“Thou hast conquered, O pale Galilean; the world has grown grey from thy breath;
We have drunken of things Lethean; and fed on the fullness of death.
Laurel is green for a season, and love is sweet for a day;
But love grows bitter with treason, and laurel outlives not May.
Sleep, shall we sleep after all? for the world is not sweet in the
end;
For the old faiths loosen and fall, the new years ruin and rend.”
—A.C. (Algernon Charles)