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:
“Dear, be the tree your sleep awaits;
Worms be your words, you not safe from ours.”
—John Ashbery (b. 1927)
““You might just as well say,” added the Dormouse, which seemed to be talking in its sleep, “that ‘I breath when I sleep’ is the same thing as ‘I sleep when I breathe’!””
—Lewis Carroll [Charles Lutwidge Dodgson] (1832–1898)
“A speckled cat and a tame hare
Eat at my hearthstone
And sleep there;
And both look up to me alone
For learning and defence
As I look up to Providence.”
—William Butler Yeats (1865–1939)