Pineal gland is an endocrine gland ,write its role

Explanation

1. In human ,the pineal gland is located behind the third ventricle of brain
2. It secretes the hormone .melatonin which plays a central role in the regulation of circadian rhythm of our body and maintains the normal sleep wake cycle.
3. It also regulates the timing of secual maturation of gonads.
4. In addition melatonin also influences metabolism , pigmentation, menstrual cycle and defence mechanism of our body