Term
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Definition
| excitable cells within the nervous system, use their excitability as a means of communication |
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Term
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Definition
| Non-excitable, support cells for the nervous system |
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Definition
| Glial cells that perform all glial functions EXCEPT myelinating |
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Definition
| Glial cell responsible for myelin coating within CNS |
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Definition
| Glial cell responsible for myelin coating within PNS |
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Term
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Definition
| Spaces between myelin sheaths on axon |
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Term
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Definition
| Another name for the cell body of the neuron |
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Definition
| branching, receptive portion of neuron |
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Definition
| conducting element of neuron, up to 1 meter in length |
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Term
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Definition
| projection off of the neuron cell body - either dendrite or axon |
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Term
| Pre-synaptic terminal area |
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Definition
| transmitting element of neuron |
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Term
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Definition
| Neurons form the basic signalling units of the NS, and are distinctly bound cells |
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Term
| Principle of Dynamic Polarization |
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Definition
| Info within NS flows in a specific direction - always presynaptic to postsynaptic |
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Term
| Principle of connection specificity |
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Definition
a) No cytoplasmic continuity between cells
b) Do NOT connect indiscriminately
c) Rather, each neuron cell makes specific connection with some targets, and not others |
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Term
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Definition
| one single neurite coming off the cell body. Typically only found in invertebrates. |
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Term
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Definition
2 neurites coming off cell body.
Tend to be SENSORY information (project back towards CNS) |
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Term
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Definition
| more than 2 neurites coming off cell body - example: spinal motor neuron |
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Term
| 3 major classifications for neurons based on functionality |
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Definition
1) Afferent - sensory, project towards CNS
2) Efferent - motor, move out from CNS
3) Interneurons - project between afferent and efferent neurons, largest number of functional neurons within system |
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Term
| functions of Glial cells (list 7) |
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Definition
1) support - provide firmness and structure
2) form Myelin (Oligodendrocyte and Schwann cell)
3) scavengers - remove debris after injury/disease within CNS
4) buffers - maintain extracellular environment (Na&K) during high neuronal activity
5) During development, guide migration of neurons
6) form Blood Brain Barrier
7) possible nutritive value |
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Term
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Definition
Act as immune system - normal phagocytes are too big
mobilized after injury, infection, and some diseases |
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Term
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Definition
| Oligodendrocytes, Schwann cells, and Astrocytes |
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Term
| Fast Anterograde Axonal transport (forward moving) |
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Definition
Most newly synthesized organelles (mostly synaptic vesicles) within axon and dendrites transported this way. Move from 400-1000 mm/day.
Relies on protein Kinesin to transport organelles. |
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Term
| Slow Anterograde Axoplasmic Transport |
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Definition
Cytosol transported down axon by this form of transport. Moves at rate of 3 mm/day, carries proteins used to make up fibrillar elements of cytoskeleton.
Doesn't require extra energy, since elements travel with current. |
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Term
| Fast Retrograde Transport |
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Definition
Returns materials from terminals to cell body for degradation or restoration and reuse. Travel at a rate of about 200-400 mm/day.
Travel along microtubules, relying on action of protein Dynin. |
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