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:
“It is only when we speak what is right that we stand a chance at night of being blown to bits in our homes. Can we call this a free country, when I am afraid to go to sleep in my own home in Mississippi?... I might not live two hours after I get back home, but I want to be a part of setting the Negro free in Mississippi.”
—Fannie Lou Hamer (1917–1977)
“Still it cried, “Sleep no more!” to all the house:
“Glamis hath murdered sleep, and therefore Cawdor
Shall sleep no more, Macbeth shall sleep no more!””
—William Shakespeare (1564–1616)