Basic Nervous System Anatomy
The main parts
Central and peripheral nervous systems
The nervous system is divided into the central nervous system CNS and the peripheral nervous system PNS. The CNS includes the brain and spinal cord. The PNS includes all nerves outside the brain and spinal cord.
Nervous system organization
| Part | Main role |
|---|---|
| Brain | Processes information and controls thinking, movement, and body functions |
| Spinal cord | Carries signals between brain and body |
| Peripheral nerves | Carry messages to and from the CNS |
Useful picture to remember
Think of the brain as the control center, the spinal cord as the main highway, and the nerves as local roads.
Anatomy terms
Which structure belongs to the central nervous system?
The central nervous system includes the brain and spinal cord.
Correct answer: Brain
What does PNS stand for?
PNS means peripheral nervous system, which includes nerves outside the brain and spinal cord.
Correct answer: peripheral nervous system
Sensory vs motor pathways
Sensory pathway
- Carries information from body to brain
- Example: feeling touch or pain
Motor pathway
- Carries commands from brain to muscles
- Example: lifting your hand
Which direction do sensory signals usually travel?
Sensory signals carry information from the body toward the brain and spinal cord.
Correct answer: From the body toward the CNS