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:
“I am Anne Rutledge who sleep beneath these weeds,
Beloved in life of Abraham Lincoln,
Wedded to him, not through union,
But through separation”
—Edgar Lee Masters (1869–1950)
“Not until just before dawn do people sleep best; not until people get old do they become wise.”
—Chinese proverb.
“The place became full of a watchful intentness now; for when other things sank brooding to sleep the heath appeared slowly to awake and listen. Every night its Titanic form seemed to await something; but it had waited thus, unmoved, during so many centuries, through the crises of so many things, that it could only be imagined to await one last crisis—the final overthrow.”
—Thomas Hardy (1840–1928)