2006-12-07 02:26:54 · 3 answers · asked by Anonymous in Science & Mathematics ➔ Medicine
Your eye lids are heavy because you did not get enough sleep, your body needs at least 8 hours of sleep everynight to get started again the following day, Your nervous system was active for several hours and that is why you are feeling the way you do, when your eyes are closed your postural muscles are relaxed and consciousness practically suspended, and you do not loose any blood or oxygen from your brain.
2006-12-07 02:56:45 · answer #1 · answered by Brie 2 · 0⤊ 0⤋
No, cerebral blood flow and oxygen delivery are not changed. You will sleep. Put it off if you want, but eventually your deeper brain functions will veto the idea of staying awake. You might want to do a web search on the reticular activating system.
2006-12-07 05:11:45 · answer #2 · answered by Anonymous · 0⤊ 0⤋
your eyes become heavy because it is the body's defense. when your body needs sleep it starts to basically shutdown and forces your eyes to close so you will sleep and it is the bodys way to try to shut down so it can revive its cells. while you sleep your body fixes itself and enables you to continue. if your eyes get heavy, listen to your body and go to sleep.
2006-12-07 02:35:51 · answer #3 · answered by annbongio 1 · 0⤊ 0⤋