Autonomic system
Brain
Spinal cord
Somatic system
Nerves
it has plenty of nerves that connect to every organ.
Nerves that send information from the senses to the brain.
Nerves that control involuntary movements and functions of the body such as digestion, breathing, etc.
It is in charge of sending and receiving messages through the nerves.
are made of millions of neurons that send messages from the parts of the body to the brain and vice versa.