What is melatonin? What is its role in human physiology?

1 Answer
Oct 16, 2016

Melatonin is the hormone which makes the body sleep.

Explanation:

A key factor in how human sleep is regulated is exposure to light or to darkness. The exposure of the human eye to light makes movement in a nerve from the retina to the suprachiasmatic nucleus (SCN).
From here the instructions are given to others parts of the brain which control the hormonal release.

Pineal gland-
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Melatonin is a hormone which is produced by the Pineal gland. It is very small and is located just above the middle of the brain. During day time Pineal gland is inactive because it has no work.

For Sleeping:
When Darkness occurs around and our eye senses it then it sends a Signal through from the retina through a nerve to the Brain part SCN.

The SCN then transmits it to all the other parts of the brain. This makes release of Melatonin in the blood stream.
Rise in levels of Melatonin in the blood stream makes us feel drowsy and sleepy.
This happens around 9 pm and works for about 12 hours.

For Waking:
After this at about 9 in the morning the Melatonin level gradually decreases from the blood level and we completely wake up from inside of our body too.

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When you have sleep disorders you are given Melatonin supplements to sleep properly.
Overdose of the drug can even take the human body to coma.