Physiology 2130 Lecture Notes - Lecture 6: Medulla Oblongata, Frontal Lobe, Premotor Cortex
Document Summary
The nervous system consists of the cns (central nervous system) and the pns (peripheral nervous system). The cns is made up of the brain and spinal cord, while the nerves outside that go to muscles/organs are considered part of the. We can divide the pns into the somatomotor (going to skeletal muscles) and autonomic (going to other organs) nervous systems. Contains between 10 and 100 billion cells, and weighs roughly 1. 5 kilos (3. 5 lbs). Laid out end to end, the cells of the brain would stretch about 1000 km. One has more brain cells when they are born, than as an adult. Action potentials (language of the nervous system) can travel down neurons at up to 400 km per hour. It is divided into two hemispheres that control bodily function mostly through bilateral innervation (sensory information from the right side of the body travels to the left hemisphere).