Membrane Processes
Ion Channels
Graded Potentials
All Things Propagation
Misc.
100
Transmembrane potential of a resting (undisturbed) cell
What is Resting Potential
100
Also referred to as ligand-gated channels. Open or close in response to a specific chemical stimulus
What are Chemically-gated Channels
100
Graded potentials occur most often in the _____ and ____ of a neuron
What are dendrites and cell body
100
When voltage-gated Na+ channels close, what voltage-gated channels open?
What is K+
100
Given stimulus either triggers an action potential, or none at all.
What is All-or-None Principal
200
Stimulus produes a temporary localized change in the resting potential. Th effect decreases with the distance from the stimulius
What is Graded Potential
200
Open or close in response to a change in the transmembrane potential
What are Voltage-gated Channels
200
As the current moves away from the site of stimulation, what does depolarization do?
What is Decreases
200
AP can be generated- requires a stronger stimulus than normal
What is Relative Refractory Period
200
Direct physical contact between cells. No neurotransmitters. Conduction is faster than a chemical synapse
What is Electrical Synapse
300
If a stimulus is strong enough, a graded potential results in an action potential.
What is Action Potential
300
Channels randomly open and close. Neurons have more K+ than Na+ channels
What are Leaky Channels
300
Restores the normal resting membrane potential after depolarization
What is Repolarization
300
An action potential spreads (propagates) over the surface of what membrane
What is the Axon Membrane
300
Cells are not in direct contact with one another. AP may or may not be progagated to the postsynaptic cell
What is Chemical Synapse
400
Release of neurotransmitters in the presynaptic membrane
What is Synaptic Activity
400
Respond to mechanical vibration or pressure
What are Mechanically-gated channels
400
Stimulus opens gated K+ channels. K+ leaves the cell
What is Hyperpolarization
400
Occurs in myelinated axon. Depolarization only at the Nodes of Ranvier
What is Saltatory Conduction
400
Cause hyperpolarization of the postsynaptic membrane. Suppresses AP
What is Inhibitory Neurotransmitters
500
Response of the postsynaptic cell depends on the "message" from the presynaptic cell as well as stimuli from other cells
What is Information Processing
500
What concentration of ions are found outside of the cell
What is Na+ ions and Cl- ions
500
What is the resting membrane potential of a neuron
What is -70mV
500
Thicker axons have more voltage-gated channels
What is Axon diameter
500
Enzyme from the postsyaptic neuron breaks down neurotansmitter
What is Enzymatic Breakdown
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