302205
Pineal gland of human brain secretes melatonin concerned with
1 Colouration of skin
2 Sleep
3 Anger
4 Body temperature
Explanation:
The pineal gland secretes melatonin which is a hormone that help regulate circadian rhythms. Melatonin is produced according to the amount of light a person is exposed to. The pineal gland releases greater amount of melatonin when it is dark which point to melatonin role in sleep.