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:
“Paul loved to sleep with his mother. Sleep is still most perfect, in spite of hygienists, when it is shared with a beloved.”
—D.H. (David Herbert)
“Oh Sleep! it is a gentle thing,
Beloved from pole to pole!
To Mary Queen the praise be given!
She sent the gentle sleep from Heaven,
That slid into my soul.”
—Samuel Taylor Coleridge (1772–1834)
“Bunched upside down, they sleep in air.
Their sharp ears, their sharp teeth, their quick sharp faces
Are dull and slow and mild.
All the bright day, as the mother sleeps,
She folds her wings about her sleeping child.”
—Randall Jarrell (1914–1965)