CNS Vs PNS

CNS

• Brain, spinal cord, and Brain stem 
• Function:
  • Main control center 
  • Protected by meninges, cerebral spinal fluid, skull and vertebra 
  • Types of matter 
    • White matter is "inside" the brain that are umyelinated neurons 
    • Gray matter is "outside" with myelnated neurons 

PNS

• 12 Cranial nerves and 31 pairs of spinal nerves (5 cervical, 12 Thoracic, 5 lumbar, 5 sacral, 1 coccygeal) 
• Function:
  • Anterior root 
    • Carries info away from CNS in spinal nerves (Efferent) 
  • Posterior root 
    • Carries info towards CNS in spinal nerves (Afferent) 
  • Autonomic nervous system (ANS)
    • Sympathetic division
      • Emergency response 
      • Fight or flight 
      • Norepinephrine neurotransmitter to create a response  
    • Parasympathetic division 
      • Relaxation
      • Restores energy 
      • Acetylcholine neurotransmitter to relax the body