The structure that serves as our biological clock and controls our circadian rhythms is _______________.
A) the heart with its pacemaker cells
B) the pituitary gland
C) the pineal gland
D) the suprachiasmatic nucleus

Question

Quizplus · Accepted Answer

The suprachiasmatic nucleus is a tiny structure in the brain that generates circadian rhythms with the help of external cues such as light and darkness. It is considered the biological clock of the body. Option A is incorrect because while the heart has pacemaker cells that regulate its own contractions, it does not control our circadian rhythms. Option B is incorrect because the pituitary gland is responsible for releasing hormones that regulate various bodily functions, but not circadian rhythms. Option C is incorrect because the pineal gland produces the hormone melatonin, which helps regulate sleep and wake cycles, but it is not solely responsible for controlling circadian rhythms.

The Structure That Serves as Our Biological Clock and Controls