Term
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Definition
| long; narrow extensions, increase the cells surface area |
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Term
| The Cell body can also be called... |
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Definition
soma
or
perikaryon
are alternate names for..
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Term
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Definition
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Term
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Definition
| rough endoplasmic reticulum which synthesizes proteins; very dominant in neurons |
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Term
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Definition
| single axon in a multi polar neuron which extends from a small area of the cell body |
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Term
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Definition
| contains a few mirochondria and the distal ends of the axon's cytoskeleton; a swellin @ the end of telodendron |
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Term
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Definition
the terminal bouton
&
postsynaptic membrane |
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Term
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Definition
| characteristic that is well developed & specalized in neurons, allowing a cell to react to its environment |
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Term
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Definition
when the cell's cytosol is electrically negative relative to the extracellular fluid around
-70mV "polarized" |
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Term
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Definition
| when a neuron is polarized it is... |
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Term
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Definition
| when there is a depolarization of about 15 to 30 mV at the axon hillock |
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Term
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Definition
| when the resting potential becomes less than -70mV, becoming more positive |
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Term
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Definition
| wave of negativity in which there is a sudden opening of ion channels and a rapid flow of (+)sodium |
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Term
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Definition
| an action potential exists or it does NOT; there is NO inbetween |
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Term
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Definition
| a decrease in membrane potential towards the resting state |
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Term
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Definition
if the restinf potential becomes greater then -70 mV
(more negative)
ex/ -90mV |
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Term
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Definition
maintains a chemical as well as an electrical gradient
-the resting membrane potential is re-established |
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Term
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Definition
glial cells in CNS
schwann cells in PNS
-facilitate the activity of the neurons |
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Term
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Definition
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Term
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Definition
| produce myelin in CNS cells & cover multiple processes around different axons |
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Term
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Definition
| role in maintaining nerve signals, protective role in blood brain barrier (BBB), repair andscarrin in the NS and secrete neurotophic growth factors |
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Term
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Definition
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Term
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Definition
| produce myelin in PNS & cover a single axon, in a "jelly roll" fashion |
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Term
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Definition
| line the ventricle & central canal of the spinal cord & are associted w/ choraic plexus/cerebral spinal fluid(CSF) & helps to form a blood (CSF)barrier |
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Term
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Definition
| responsible for the production of cerebral spinal fluid (CSF) |
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Term
Myelination -->
axon's myelin sheath |
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Definition
| when a layer wraps around an axon, multiple times |
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Term
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Definition
| axon is NOT covered by myelin; tiny space between one satellite cell and another |
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Term
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Definition
| when action potentials are not propagated continuously along a myelinated axon, instead jump from the sodium channels @ 1 node of ranevier to another |
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Term
Gogli Type I
(projection neurons) |
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Definition
| large neurons w/ long axons that project to distant portions od the nervous sytem |
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Term
Gogli Type II
(local circut neurons) |
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Definition
| small neurons in the CNS w/ short axons; do NOT extend to other parts of the NS |
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Term
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Definition
the most numerous of neurons; belongs to two types :
Gogli type I
Gogli type II
ex/ motor neurons |
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Term
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Definition
a nerve cell w/ a single process
ex/ sensory neurons |
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Term
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Definition
dendrite & axon arise from opposite end of the cell body
(two processes)
1.extend towards CNS
2. extend towards PNS |
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Term
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Definition
more portions of the skeleton & usually under voluntary control
(striated) |
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Term
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Definition
found in walls or hollow contracting organs
-non voluntary
-non striated
-single nucleus |
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Term
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Definition
found only in the heart
-non voluntary
-striated
-single nucleus
-intercaleted disks |
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Term
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Definition
| w/i the CNS, their cell bodies lie higher in the CNS center & their axons go to lower motor neurons |
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Term
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Definition
cell body in spinal cord or brain stem
-goes to organ, gland or muscle
(2 types)
1. alpha motor neurons
2.gamma motor neurons |
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Term
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Definition
| skeletal muscle cells are innervated by large multi-polar neurons |
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Term
| Sense organs send 3 messages to the CNS.. |
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Definition
1. degree of stretch of muscle
2. tension on each muscle
3.position of each joint
are the 3 messages this organ sends to the CNS |
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Term
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Definition
| w/i the spinal cord; help to regulate background excitation & spinal level reflexes |
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Term
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Definition
| formed by single alpha motor neurons & the muscle cells |
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Term
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Definition
| sense organs w/i the muscles, tendons and joints |
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