IB Biology HL C3.1.11 focuses on pineal melatonin secretion and circadian sleep timing. Past-paper questions ask you to identify its role and apply the light-dark cycle to jet lag.
Melatonin helps to control circadian rhythms in the body. The graph shows the mean levels of melatonin in the body in day and night workers over 24 hours.
State where melatonin is produced in the body.
pineal gland;
Deduce, with a reason, what time of day would be a good time to take melatonin if you have travelled over several different time zones and are jet-lagged on your arrival.
Time of day: around 18:00 (locally);
OR time that is in the range of local standard bed time;
Reason: need to re-establish the increase that occurs after 18:00 hours / reestablish circadian rhythm;