AP BIOLOGY

Detailed explanation-1: -One example of a light-related circadian rhythm is sleeping at night and being awake during the day.

Detailed explanation-2: -Circadian in Latin means “around or approximately” (circa) “a day” (diem). Circadian rhythm is the name given to your body’s 24-hour “internal clock.” This internal clock controls your body’s sleep-wake cycle.

Detailed explanation-3: -As night falls, the master clock initiates the production of melatonin, a hormone that promotes sleep, and then keeps transmitting signals that help us stay asleep through the night. In this way, our circadian rhythm aligns our sleep and wakefulness with day and night.

Detailed explanation-4: -The body’s circadian rhythms control the sleep-wake cycle. They play a role in sleep due to how the body and brain respond to darkness, which is when most humans feel tired and tend to sleep. As darkness sets in, the body’s biological clock instructs the cells to slow down .