1st question: One of the most important systems in your body, the nervous system is your body's control system. It sends, receives, and processes nerve impulses throughout the body. These nerve impulses tell your muscles and organs what to do and how to respond to the environment.
2nd question: The heart is by far, the most important muscle of the human body. The heart is a pump, composed of muscle which pumps blood throughout the body, beating approximately seventy-two times per minute.
