PNS Flashcards
PNS function
carries information to and from the CNS
afferent nerves
travelling to the CNS
efferent nerves
travelling from the CNS
autonomic neurones have __ outside the spinal cord
ganglia
ganglia
collections of cell bodies, where axons synapse
how many neurones does it take for the autonomic nervous system to reach its target
two (pre and post ganglionic)
autonomic neurones arise from the __
brain and the spinal cord
where are sympathetic cell bodies present
thoracic and lumbar spinal cord segments
thoracic and lumbar spinal cord segments connect to __
paravertebral ganglion chain, the sympathetic chain, or to individual ganglia
how are parasympathetic ganglia different to sympathetic
they aren’t grouped in a chain, instead they are found near the target organ
where do parasympathetic neurones arise
cranial nerves / limbo-sacral spinal cord
somatic nervous system is responsible for
conscious control of the body
role of somatic sensory nerves (afferent)
detect pain, temperature, touch and proprioception
role of somatic efferent nerves
motor to effector skeletal muscles
order of transmission
brain (Precentral gyrus), spinal cord (Corticospinal tract), axon, neuromuscular junction
nerves can be either __ or __
spinal, cranial
spinal nerves
carry axons of neurones (somatic and autonomic) to and from the spinal cord
where do spinal nerves leave the spinal cord (except the cervical region)
below each vertebrae
which vertebrae has a cervical nerve above and below
C7
each spinal nerve has a __ and a __
dorsal root and a ventral root
dorsal root
afferent/sesnsory
ventral root
efferent/motor
plexus
network of vessels/nerves
when do nerves begin to blend into other never (plexus)
after leaving the spinal cord
lumbar plexus
vertebrae T12-L5
dermatome
area of skin
myotome
group of muscles
Each spinal nerve supplies and is supplied by __
a dermatome / myotome
how is distribution of a spinal nerve different to distribution of a peripheral nerve
peripheral nerve can have more than one dermatome
sciatic nerve muscles
motor to muscles of posterior thigh
sciatic nerve motor
sensory afferent from the skin over the lateral side of leg
femoral nevre muscles
motor to muscles of anterior thigh
femoral nerve motor
sensory afferent from anterior thigh and medial leg
what do cranial nerves supply
special senses e.g. taste
