Biological Approach Revision

A circadian rhythm is like a

• 24 hour biological cycle

• an exogenous zeitgeber

• a part of the brain

• time giver

Fill in the blank to begin discussing the role of the brain in sleep, "First, the ___ sends signals to the SCN that sunlight is decreasing"

Finish this sentence, "As sunlight decreases, the SCN sends signals to the..."

Next, the pineal gland begins to release...

Melatonin is released into the bloodstream. Once sleep is underway, melatonin slowly _____ into the morning.

A break pedal is applied to the ____ ____ which slowly shuts of the release of melatonin.