Pineal Gland
The Pineal Gland, also known as the pineal body, is a small endocrine gland in the brain. It produces melatonin, a serotonin derived hormone, that affects the modulation of sleep patterns in both seasonal and circadian rhythms. Its shape resembles a tiny pine cone (hence its name), and it is located in the epithalamus, near the centre of the brain.
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