Flashcards in Electrical Neural Communication Deck (88)
Hyperpolarization of dendrites and cell body
These gates open near the peak of the action potential and close during after-hyperpolarization
Vg potassium channels
A measure of a difference in electrical potential
What are some different ion pumps?
Tool that visualizes voltage change over time
Can measure or record activity and can deliver electrical current (stimulate)
When is electrochemical equilibrium achieved?
When the electrical force and concentration force are balanced. The net flux is 0
Combines input to same location over time. Changes how fast the input is
Electrical force and concentration force want this ion to go in the cell, but the cell doesn't want it
Usually due to the inward flow of chloride ions or outward flow of potassium ions (rare)
Dendrites do not have this
Is the inside of an axon positive or negative?
The neuron can fire with a stronger stimulus, AP less likely. K channels are still open, effluxing out; too much K comes out making it go beyond resting
Relative refractory period
If the membrane potential becomes more positive than its is at the resting potential, the membrane is said to be this
Protein structure in cell membrane that uses energy (ATP) to move ions across the membrane. Like a salmon swimming upstream
What are the different types of ion channels?
Ratio of intracellular ions
Large amounts of potassium ions. Small amounts of sodium and chloride
The decision point of the cell
Features of the resting potential
Neuron is polarized
Charge is around -70 mV
Selectively permeable membrane
Uneven distribution of ions on the inside vs the outside
What cations are involved with axons?
Potassium, sodium, and calcium
Increase in electrical charge across a membrane (more negative)
Limits how frequently a neuron can fire, maintains unidirectionality of signals
A device that measures the difference in electrical potential between two bodies
Small analogue signals summed over time and space
These negatively charged molecules are unable to pass through channels and pumps
What is the resting potential value for most neurons?
This toxin is found in pufferfish and block VG Na channels and prevents the flow of sodium. It prevents the rising phase of AP and causes death by paralysis
Charge of the threshold
Around -60 mV
Selectively binds to VG Na channels to stop the flow of NA. Prevents the rising phase of AP. No sensory or motor function
Local anesthetics. Novocaine, lidocaine, -caine