PNS Flashcards
What is the name of the nervous system branch that controls voluntary movement
Somatic
What is the name of the nervous system that controls involuntary responses
Autonomic
Within the visceral nervous system, what is the difference between the sympathetic and parasympathetic branches
Symp-Fight or flight
-Mobilises bodily systems
-efferent nerves innervate the viscera (organs) and periphery (vasculature and sweat glands)
Parasymp
-Conserves energy
-Efferent nerves innervate the viscera (organs) only
How many pairs of cranial and spinal nerves are there?
12 CN
31SN
What is a dermatome and myotome
Dermatome: An area of skin supplied by a single spinal nerve
Myotome: Group of muscles innervated by a single spinal nerve
What is a nucleus
A collection of neurone cell bodies within the CNS
What is a ganglion
A collection of neurone cell bodies outside the CNS
What is a plexus
A network of interconnected nerves
Where do afferent (somatic and visceral) fibres have their cell bodies
Spinal ganglia
Where do visceral efferent nerves synapse
Peripheral ganglion
Give the overall outline for the PNS branches
Give the gross anatomy of a spinalnerve incl the 3 connective tissue layers
Three layers of connective tissues
External vascular layer - epineurium
Individual fascicles covered in perineurium
Individual axons covered in endoneurium
How are nerve fibres classified
Conduction velocity (A,B,C. A is fastest)
Axonal diameter (I-IV. I is largest)-Only sensory are measured
Give the 5 sensory neurone types(by type of detection)
Chemoreceptors
Thermoreceptors
Photoreceptors
Mechanoreceptors
Nocireceptors
Give the classification of types of receptors and what they detect
External
-Exteroreceptors
(Pain, temp, touch, pressure)
Internal
-Proprioeptors
(Movement, joint position)
-Enteroceptors
(Movement through gut, pH)
Give an example of where’ you’d find chemoreceptors
Detector molecules which bind to receptor e.g in olfactory bulb