Electrophysiology of Neurons - Lecture Notes

Flashcards based on key concepts from the Electrophysiology of Neurons lecture notes.

Neuron

The basic functional units of the nervous system, specialized for excitability, conductivity, and secretion to transmit electrical and chemical signals.

Neuroglia

Supportive cells that outnumber neurons 10 to 1, providing structural support, myelination, immune defense, and metabolic support in the CNS and PNS.

Saltatory Conduction

The process by which myelinated axons conduct neural signals more efficiently, allowing for rapid transmission of action potentials.

Resting Membrane Potential

The stable charge/voltage of the plasma membrane of a neuron in an unstimulated state, typically around -70mV.

Action Potential

A dramatic change in membrane polarity produced by voltage-gated ion channels that represents an all-or-nothing response.

Depolarization

The process of the membrane potential becoming more positive; occurs when Na+ ions enter the neuron.

Repolarization

The process of returning the membrane potential to its resting state after depolarization, involving K+ ions exiting the neuron.

Hyperpolarization

A state where the membrane potential becomes more negative than the resting potential due to K+ ions leaving the cell.

Graded Potentials

Localized changes in a cell’s membrane potential that can vary in magnitude and strength based on stimulus intensity.

Voltage-gated Channels

Channels that open and close in response to changes in membrane potential, primarily found along the axon.

Ligand-gated Channels

Channels that open when a specific chemical (ligand) binds to the channel, primarily found on dendrites and the soma.

Local Potential

Short-range changes in membrane voltage that occur at stimulated sites and can influence action potentials.

Sodium-Potassium ATPase Pump

A membrane protein that maintains the resting membrane potential by moving 3 Na+ ions out of the cell for every 2 K+ ions it brings in.

Threshold Potential

The level of depolarization that must be reached to trigger an action potential.

Summation

The process by which multiple graded potentials combine to influence the likelihood of an action potential being generated.