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Kaila Simmons
Physiology Weeks 1-6
Term | Definition |
---|---|
What is resting membrane potential? | membrane potential maintained by a nonconducting neuron's plasma membrane |
What are local potentials? | a shift away from the RMP in a specific region of the plasma membrane |
What is another name for a local potential? | Graded potential |
What are stimulus-gated channels? | ion channels that open in response to chemicals produced by a sensory stimulus or a chemical stimulus received by another neuron |
What are ligand-gated channels? | These are triggered by ligands, which are signal molecules that bind to a receptor |
What is depolarization? | movement of the membrane potential toward zero |
What is hyperpolarization? | movement of the membrane potential away from zero |
What is an action potential? | The membrane potential of an active neuron; one that is conducting an impulse |
First 3 steps of the mechanism that produces an action potential | 1. stimulus triggers stimulus-gated Na+ channels to open and allow inward Na+ diffusion; membrane will depolarize 2. threshold is reached, voltage-gated Na+ channels open 3. more Na+ enters through the voltage gated channel, membrane depolarize |
Last 3 steps of the mechanism that produces an action potential | 4. magnitude of action potential peaks when Na+ channels close 5. repolarization begins when K+ channels open, allowing outward diffusion of K+ 6. hyperpolarization occurs, causing the resting potential to be restored by sodium/potassium pump |