Ch 13 - Nervous System pt 1 Flashcards
which osseous structures protect the CNS?
cranium and spinal column protect the brain and spinal cord
what are the two divisions of the PNS
somatic and visceral
where does the CNS end and PNS begin?
PNS begins at the nerve rootlets that begin to stick out of the spinal cord
what are the two divisions of the ANS?
parasympathetic and sympathetic
there are ____ times more neuroglia than neurons in nervous tissue
5
what are the neuroglia of the CNS
1) oligodendrcytes
2) microglia
3) astrocytes
4) ependymal cells
what are the neuroglia of the PNS?
1) Schwann cells
2) satellite cells
what are the 4 different neuron structural classifications
1) anaxonic
- CNS: special sense organs
- poorly understodd
- can’t tell apart cell body from dendrites
2) bipolar
- relay sight, smell, hearing
- soma in middle of two main dendrites
3) pseudo unipolar
- sensory neurons of PNS
- cell bodies found in dorsal root ganglia
- continuous axon, with cell body on the side
4) multipolar
- most common neutron in CNS
what are the 3 functional classifications on neurons?
1) sensory
- afferent division of PNS
- relay info from receptors to CNS
- somatic and visceral sensory neurons
- 3 types: interoceptor, exteroceptor, proprioceptor
2) motor
- efferent division of PNS
- somatic and visceral
- relay info to effectors
- cell bodies in CNS (preganglionic) and PNS (post)
3) interneurons
- in CNS (mostly)
what are the steps of a chemical synapse?
1) AP depolarizes axon terminal
2) depolarization opens voltage gated Ca++ channels; Ca++ enters cell
3) Ca++ entry triggers exocytosis of synaptic vesicle contents; contents go into synaptic cleft
4) neurotransmitter diffuses across synaptic cleft and binds with receptors on post-synaptic cell
5) binding initiates response in post-synaptic cell
review neuron organization and processing
p 353
