Samenvatting Physiology - Peripheral Nervous System

Physiology notes

Central Nervous System (CNS)
 Brain
 Spinal cord
Peripheral Nervous System (PNS)
 Located outside of the skull and spine
 Serves to bring information into the CNS and carry signals out of the
CNS

Peripheral Nervous System
o Somatic nervous system
 Transmits signals to and from the central nervous
system
 Afferent nerves (sensory)
 Efferent nerves (motor)
o Autonomic nervous system
 Controls function of organs and glans
 Sympathetic and parasympathetic nerves
 Sympathetic = flight fight response
 Parasympathetic = restores body to a state of
calm
 Both afferent and efferent nerves
 Efferent: Sympathetic and parasympathetic nerves
o Sympathetic = flight fight response
o Parasympathetic = restores body to a state
of calm
Enteric nervous system in digestive tract.
Autonomic nervous system
- Innervates systems that cannot be controlled by the conscious brain
(heart, smooth muscle, blood vessels, most visceral organs, all
endocrine glands)
- Nervous parasympathetic and sympathetic system
- Sympathetic = increased heart rate (catabolic processes)
- Parasympathetic = vasodilation, energy substrates stored in
glycogen, fat and muscle (anabolic processes)
Sympathetic Parasympathetic
Originates in spinal cord Originates in brain stem
Dilates pupils Constricts pupils
Stops secretion of saliva Saliva production
Dilates bronchioles Constrict bronchioles

- Antagonistic neurons control heart rate: some speed it up, others
slow it down
- Parasympathetic via nervus vagus and only on frequency
(pacemaker), sympathetic via cardiac nerve and influences
frequency + contraction.