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2006-09-22 09:22:33 · 16 answers · asked by doorseeker 1 in Science & Mathematics ➔ Medicine
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WXY AND ZZZZZZZZZZ..
2006-09-22 09:33:37 · update #1
If you know your A B ZZZZZ.. You will know why people ZZZZZ..
2006-09-27 08:46:13 · update #2
A circadian rhythm is a roughly-24-hour cycle in the physiological processes of living beings, including plants, animals, fungi and cyanobacteria. The term "circadian", coined by Franz Halberg, comes from the Latin circa, "around", and dies, "day", meaning literally "about a day." The formal study of biological temporal rhythms such as daily, weekly, seasonal, and annual rhythms, is called chronobiology.
2006-09-22 14:32:41 · answer #1 · answered by Emerson 5 · 1⤊ 0⤋
Nerve-signaling chemicals called neurotransmitters control whether we are asleep or awake by acting on different groups of nerve cells, or neurons, in the brain. Neurons in the brainstem, which connects the brain with the spinal cord, produce neurotransmitters such as serotonin and norepinephrine that keep some parts of the brain active while we are awake. Other neurons at the base of the brain begin signaling when we fall asleep. These neurons appear to "switch off" the signals that keep us awake. Research also suggests that a chemical called adenosine builds up in our blood while we are awake and causes drowsiness. This chemical gradually breaks down while we sleep.
2006-09-22 09:34:00 · answer #2 · answered by Diana 6 · 1⤊ 0⤋
Accumulation of a substance called Muramyl Peptide in the brain leads to the inhibition of a part of the brain called as the Reticular Activating System (RAS) which results in drowsiness and on getting fully inhibited leads to sleep. This is the most widely accepted theory though many other theories with considerable evidences exist.
2006-09-22 23:31:39 · answer #3 · answered by labyrinth 3 · 0⤊ 0⤋
We have to sleep because it is essential to maintaining normal levels of cognitive skills such as speech, memory, innovative and flexible thinking.
In other words, sleep plays a significant role in brain development.
:)
2006-09-22 11:15:34 · answer #4 · answered by Psycho Babe 1 · 2⤊ 0⤋
Working with Yahoo!Clever... No, seriously: Soft music and the ability to stop thinking!! Counting (not sheep, just so) also helps.
2006-09-22 09:31:28 · answer #5 · answered by Anonymous · 1⤊ 0⤋
It seems to me its a habit, but I don't know. Our body just needs it and sleeping is gooooooooooooooood!
2006-09-22 09:40:41 · answer #6 · answered by Earthling 7 · 1⤊ 0⤋
The chemicals in their brains. Your brain tells you you're tired, so you sleep.
2006-09-22 09:24:34 · answer #7 · answered by Anonymous · 1⤊ 0⤋
the circadian rhythm and serotonin (the sleep chemical in your brain)
2006-09-22 20:21:31 · answer #8 · answered by kayro3 3 · 0⤊ 0⤋
electrical system in your brain needs to recharge itself
2006-09-22 15:15:28 · answer #9 · answered by Nick 5 · 0⤊ 0⤋
Because we need rest.
2006-09-30 02:27:56 · answer #10 · answered by Anonymous · 0⤊ 0⤋