Neurons, Glia, and Nervous Systems

A set of flashcards covering key vocabulary and concepts related to the structure and function of neurons, glial cells, and the nervous system.

Neuron

A nerve cell that generates and conducts electric signals.

Glia

Supportive cells in the nervous system that modulate neuron activity.

Action Potential (AP)

A rapid change in membrane potential that generates an electrical signal in neurons.

Synapse

The junction between two neurons where information is transferred from the presynaptic cell to the postsynaptic cell.

Neurotransmitter

Chemicals released by neurons that transmit signals to other neurons or target cells.

Resting potential

The steady state membrane potential of a neuron when it is not actively sending a signal.

Oligodendrocytes

Glial cells that wrap around axons in the central nervous system to form myelin.

Schwann cells

Glial cells that wrap around axons in the peripheral nervous system to produce myelin.

Potassium channels

Ion channels that allow the movement of K+ ions and are open in the resting membrane.

Refractory period

A period following an action potential during which a neuron cannot fire another action potential.

Saltatory conduction

The jumping of action potentials from node to node along myelinated axons, which increases conduction speed.

Dendrites

Extensions of a neuron that receive signals from other neurons.

Axon

The long projection from a neuron that transmits electrical impulses away from the cell body.

Depolarization

A decrease in membrane potential, making the inside of a neuron less negative.

Chemical synapse

A type of synapse where neurotransmitters are released from one neuron to affect another.

Graded potential

A change in membrane potential that varies in size, depending on the strength of the stimulus.

Summation

The process by which multiple excitatory and inhibitory signals are combined to determine the overall response of a neuron.

Acetylcholine (ACh)

A neurotransmitter that plays a key role in communication between neurons and muscle cells.

Action Potential Threshold

The critical level of depolarization that must be reached for an action potential to occur.