Hence, an arrow which bends less is said to have more spine. In order to strike consistently, a group of arrows must be similarly spined. Center-shot bows, in which the arrow passes through the central vertical axis of the bow riser, may obtain consistent results from arrows with a wide range of spines.
Definition of MELATONIN. : a vertebrate hormone that is derived from serotonin, is secreted by the pineal gland especially in response to darkness, and has been linked to the regulation of circadian rhythms.See melatonin defined for kids.ADVERTISEMENT. Greek melas black + -tonin (as in serotonin).efinition of MELATONIN. : a vertebrate hormone that is derived from serotonin, is secreted by the pineal gland especially in response to darkness, and has been linked to the regulation of circadian rhythms. See melatonin defined for kids. ADVERTISEMENT. Greek melas black + -tonin (as in serotonin).
Why is Serotonin Important. Serotonin information gotten from a top notch source shows that serotonin is very important for the human health. Serotonin is a neurotransmitter released by the brainâs neurons and is produced from amino acid tryptophan.f there is a low production of serotonin in the brain, it can result in depression and fear. When serotonin is produced in the right quantity in the brain, it simply promotes feelings of contentment well being and comfort.