Gordon is having trouble sleeping and decides to take a supplement containing a hormone that is manufactured in the pineal. What is he most likely taking?
A) leptin
B) glucagon
C) melatonin
D) renin
Answer:
C) melatonin
Explanation:
Melatonin is a water-soluble hormone secreted by the pineal gland. The function of this hormone is to maintain the biological clock of the body. In the darkness, the sensory information from retina makes the suprachiasmatic nucleus to trigger the sympathetic postganglionic neurons of the superior cervical ganglion. The information from these ganglion makes the pineal gland to secrete melatonin causing sleepiness. A lesser amount of melatonin is secreted in the daytime. A person having trouble with sleeping would take melatonin supplements to regulate the biological clock.
