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The table below show factors that affect sleep patterns in humans, with locations of sleep stimulants X and Y missing from the table.
Stimulus Internal
or
External Response
Time of day X Lets the body know when it is time to go bed
Levels of chemical serotonin Y Tells the body it is sleepy or encourages alertness
What are X and Y?
A.
X is external; Y is internal
B.
X is internal; Y is external
C.
X and Y are external
D.
X and Y are internal
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The table below show factors that affect sleep patterns in humans, with locations of sleep stimulant...
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