Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
20 Cards in this Set
- Front
- Back
What are the 3 functions of the NS?
|
gather info-sensory input
process and interpret info- integration respond to info-motor output |
|
PNS
|
Functional divisions:
sensory & motor somatic- voluntary autonomic-involuntary sympathetic & parasympathetic |
|
what are the two types of cells in the NS?
|
Neurons- excitable cells that transmit electrical signals
Neuroglia, or glia- supporting cells surrounding wrapping neurons |
|
what are the glia in the CNS?
|
Astrocytes- most, support and brace neurons
microglia- monitor health of neurons ependymal cells- line central cavities, circulate cerebrospinal fluid oligodendrocytes- wrap around thicker axons to create myelin sheath |
|
what are the glia in the PNS?
|
Satellite cells- surround neuron cell bodies
Schwann cells- form myelin sheaths in PNS |
|
characteristics of neurons
|
conduct electrical nerve impulses
extreme longevity amiotic-no more high metabolic rates- needs a lot of nutrients and O2 |
|
Neuron Anatomy
|
cell body and 1 or more processes
cell body- soma rough er- nissl bodies many microtubules and neurofilaments cell body clusters- CNS=nuclei PNS=ganglia |
|
what are processes?
|
arm like projections from cell body
|
|
what are bundles of processes called? Cns?pns?
|
Tracts=CNS nerves=PNS
|
|
What are the two types of processes?
|
dendrites and axons
|
|
Dendritic spines
|
thorn like projections from dendrites
|
|
what do dendrites do?
|
conduct info TO cell body by graded potentials
|
|
how many axons per neuron?
|
1
|
|
What does the axon do?
|
generates nerve impulses(action potentials) and transmits them away from the cell body to next neuron
|
|
What don't axons have?
|
Nissl bodies or Golgi apparatus'
|
|
What do myelin sheaths do?
|
protects and insulates axons, increases speed of transmission
|
|
neurilemma
|
portion of schwann cell containing nucleau and most of cytoplasm
|
|
nodes of ranvier
|
gaps between schwann cells where axon is exposed
|
|
What color matter is in each?
|
white=CNS and gray=PNS
|
|
whats the classifications of neurons?
|
structural(# of processes)=multipolar, bipolar, unipolar
functional=sensory(afferent), motor(efferent), interneuron or association neuron |