Circadian rhythms are controlled by the
A)pineal gland.
B)suprachiasmatic nucleus.
C)thalamus.
D)hippocampus.

Question

Quizplus · Accepted Answer

The suprachiasmatic nucleus (SCN) is the master biological clock that controls the circadian rhythms in mammals, including humans. The SCN is located in the hypothalamus of the brain and receives input from light-sensitive cells in the retina that help synchronize the biological clock with the 24-hour day-night cycle. The pineal gland plays a role in regulating the sleep-wake cycle by secreting the hormone melatonin, which is also regulated by the SCN. However, the SCN is the primary control center for circadian rhythms in the body. The thalamus and hippocampus are brain structures involved in sensory processing and memory formation, respectively, but they do not directly regulate circadian rhythms.

Circadian Rhythms Are Controlled by the