Divisions of NS Flashcards
Give 3 main structures/nervous systems
Central NS, Peripheral NS, Enteric NS(gut)
Name structures of nerves from inner most to outer
Axon, myelin, endoneurium, perineurium, epineurium.
Perineurium bundles multiple axons into fascicles.
Epineurium encloses fascicles and blood vessels.
What is contained within a nerve?
Axons but no dendrites. No neuronal cell bodies. (only schwaan cells)
How many pairs of nerves are in PNS?
43
How many spinal nerves are mixed?
ALL SPINAL NERVES ARE MIXED. ( contain both sensory and motor neurons )
What cells does enteric NS contain?
neural cells of viscera
What are cranial nerves and how many are there?
Peripheral nerves of brain. 12 pairs. e.g.optic auditory
where do cranial nevres 1 and 2 form from?
forebrain
Where do cranial nerves 3-12 from from?
brainstem
WHat is nerve 10?
vagus nerve. 80% PNS outflow
What are dermatones?
Patterns of innervations of spinal nerves. relatively reproducible between individuals.
How many spinal nerves are there?
31 pairs. (5 sets)
What are the divisions of the PNS?
afferent (sensory) and efferent (motor). Somatic (conscious) and visceral (subconscious)(autonomic)
What are the differences between somatic and autonomic axons?
SOmatic motor axons go straight to muscle. Autonomic motor axons connect with another cell in ganglion (which then innervates muscle/gland)
What is the differences between pre, and post-ganglionic axons?
Pre-ganglionic-myelinated
Post-ganglionic- not myelinated.
What is the different between parasympathetic and sympathetic ganglia/fibres?
Sympathetic ganglia are near spinal chord, parasympathetic ganglia are near target. Sympathetic pre-ganglionic fibres are short, parasympathetic pre-ganglionic fibres are long.
What receptors do parasymp and symp use?
Both parasymp and symp pre-ganglionic use acetylcholine and N2 receptors.
Symp post-ganglionic receptors are adrenergic (except sweat glands)
Parasymp post-ganglionic are cholinergic.
What do 2 cerebral hemispheres do?
Right - receives sensations and controls movement from left side of body.
Left- receives sensations and controls movement from right side of body.
What does cerebellum sides do?
Motor movement control centre
Right-concerned with right side of body
left-concerned with left side of body
What tissues does visceral CNS work on?
Smooth muscle, gland and cardiac muscle
What does adrenergic mean?
work on adrenaline or noradrenaline (epinephrine and norepinephrine)
What do dorsal and ventral root contain?
dorsal- axons carrying info to spinal cord,
ventral- axons carrying info away from spinal cord.
