A neurotransmitter involved in the processes of sleep and memory, as well as other neurological functions.
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Biology Dictionary
Definition:
A hormone, also called 5-hydroxytryptamine, which has the chemical formula C10H12N2O. It is produced in the pinealgland and found in blood platelets, the digestive tract, and the brain. It is both a neurotransmitter (a substance that transmits nerve signals from neuron to neuron) and a vasoconstrictor (a substance that causes the blood vessels to narrow).
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