The Nervous System Flashcards
Which nerve fibers are myelinated?
All A nerve fibers
Which nerve fibers are unmyelinated?
All C nerve fibers
Large nerve fibers that are myelinated have _______ transmission
Faster
Which nerve fibers are the fastest conductors
“A” nerve fibers
Memory area in the brain that controls conscious action and fine tunes the subconscious
Cerebral cortex
This part of the spinal cord houses the tracts that carries information to and from the brain via the ascending and descending tracts
White matter
Part of the spinal cord where synapses occur
Gray matter
What are the 2 inbound routes tracts in the spinal cord for sensory information
Dorsal column and anterolateral column
What sensory information is taken through the dorsal column
Precision, vibration, and pressure
What sensory information is taken through the anterolateral column
Pain, head, and itch
Is cell charge usually positive or negative
Negative
Where does depolarization occur?
Nodes of Raniver
After depolarization when the cell membrane has not sufficiently repolarized to allow for another depolarization regardless of stimulus
Absolute refractory period
After depolarization when repolarization is not complete but the minimum threshold for depolarization has been met
Relative refractory period
The influx of what molecule causes depolarization
Sodium
Primary excitatory neurotransmitter
Glutamate
Primary inhibitory neurotransmitter
Gamma aminobutyric acid (GABA)
Cation channels are opened by what type of neurotransmitter and allow the movement of what type of ions?
Excitatory; positive
Anion channels are opened by what type of neurotransmitter and allow the movement for what type of ion?
Inhibitory; negative
This type of receptor is one by an electrical signal
Voltage-gated
This type of receptor is opened by the binding of a substance
Ligand-gated
This type of receptor moves to activate a 2nd messenger after its initial activation (can be ligand or voltage)
G-protein coupled receptor
Increased stimulation by a NT or chronic block cause additional receptors to form on the post-synaptic membrane (often referred to as a tolerance with meds)
Upregulation
This can occur to receptor when they stay open or overactive causing fatigue
Receptor overstimulation
What subunits does ACh bind in the neuromuscular junction
2 alpha subunits
What breaks down ACh
Aceyltcholinesterase
What genetic abnormality occurs in the NMJ s/t the over release of Ca by the sarcoplasmic reticulum?
Malignant hyperthermia
Where is sensory information primarily processed
Parietal lobe (thalamus)
Where does sensory information enter the spinal column
Dorsal horns
What is the excitatory NT is the spinal cord
Glutamate
What NTs are secreted to block pain signals
Serotonin and enkephalin
Overwhelming of inhibition pathways/chemically mediated enhancement of pain pathways aka pain is greater than expected
Hyperglasia
