Because it controls all other parts of your body. E.g. heart can't beat without it. Other example: you can't move your hand, because muscles are controlled by nerves.
Because it controls all other parts of your body. E.g. heart can't beat without it. Other example: you can't move your hand, because muscles are controlled by nerves.
Because it controls all other parts of your body. E.g. heart can't beat without it. Other example: you can't move your hand, because muscles are controlled by nerves.