melatonin hormone molecule. in humans, it plays a role in circadian rhythm synchronization. stylized 2d renderings and

melatonin melatonine melatonina tryptamine hormone circadian rhythm synchronization sleep time timing receptor disorder drug pineal gland clock daynight cycle antioxidant dietary supplement food seasonal affective jet lag shift work anxiety hydrogen nitrogen carbon oxygen molecule atoms atomic model molecular compound composition chemical chemistry bond structure formula circle ring line drawing skeletal