Answer:
Central Nervous System
Spinal Cord
Peripheral Nervous System
Explanation:
The Nervous System has two MAIN parts. The Central Nervous System is made up of the brain and spinal cord.
The Peripheral Nervous System is made up of nerves that branch off from the spinal cord and extend to all parts of the body.
Hopefully, this answers's your question.
The people represented by the ends of the bell-curve are the most rare.
This could mean that if it's an iq curve the people at the ends have either a really high or really low iq etc.