The answer is It’s Pacemaker !! It is also known as the SA node
Answer:Ghrelin
Explanation:it is a hormone produced in the stomach and other parts of the gastrointestinal tract that encourage the intake of food
A study is published saying that eating broccoli disrupts sleep, while another study says that eating broccoli enhances sleep. This most resemble current research on coffee.
<h3>What does caffeine stimulate?</h3>
Caffeine is a potent Central Nervous System (CNS) stimulant, as it increases mental and alertness activity and stimulates the respiratory center. It also reduces fatigue and can increase the ability to perform certain tasks.
That's why caffeine is very researched because it stimulates the nervous system and increases mental and respiratory processes.
See more about caffeine at brainly.com/question/9255669
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