Question

Why is pineal gland also known as biological clock?

Answer 1

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The pineal gland is a tiny endocrine gland found in the brain. It produces and secretes the hormone melatonin, which is a hormone that helps regulate biological rhythms such as sleep and wake cycles. The secretion of melatonin is inhibited by light and triggered by darkness.

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Pinealocytes, neuron-like cells in the Pineal Gland, produce melatonin which is derived from serotonin. They induce rhythmic changes in the body in response to light. Melatonin levels rise at night and make us sleepy. Melatonin plays a role in our light-dark cycles and its secretion (or lack thereof) is one basis for our feelings associated with jet lag.

The responses generated by the Pineal Gland and its secretions make it the biological clock of the body.

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it regulates the melatonin production in your body via the amount of light detected by your retina. when it's dark the gland releases the melatonin which lets your body go to sleep and start "repairing" itself; also called the circadian rhythm.