Neuroglia and Neuron Function

Flashcards covering key concepts of neuroglia types, neuron function, action potentials, and related terminology.

Astrocytes

Star-shaped glial cells in the CNS that metabolize neurotransmitters and regulate K+ balance, forming the blood-brain barrier.

Oligodendrocytes

Glial cells in the CNS responsible for myelinating axons.

Microglia

The immune cells of the CNS, acting as white blood cells to clean up debris and provide defense.

Ependymal cells

Cells that line the ventricles of the brain and produce cerebrospinal fluid (CSF).

White matter

Regions of the nervous system composed of myelinated axons.

Gray matter

Regions of the nervous system composed of unmyelinated axons and neuronal cell bodies.

Myelinated nerves

Nerves that have myelin sheaths, allowing for faster transmission of neural impulses.

Unmyelinated nerves

Nerves that lack myelin sheaths, transmitting impulses much slower than myelinated nerves.

Schwann cells

Glial cells in the PNS that myelinate peripheral nerves.

Satellite cells

Glial cells in the PNS providing structural support and regulating the environment around neurons.

Action Potential (AP)

A rapid rise and subsequent fall in voltage or membrane potential across a cellular membrane.

Resting Membrane Potential (RMP)

The baseline electrical charge of a neuron, usually around -70mV.

Threshold potential

The membrane voltage that must be reached for an action potential to occur, typically around -55mV.

Absolute Refractory Period

The period during which a neuron cannot fire another action potential regardless of the stimulus.

Relative Refractory Period

The period during which a neuron can fire another action potential, but only if the stimulus is strong enough to reach threshold.

Saltatory conduction

The process of action potentials jumping from one node of Ranvier to another in myelinated neurons, speeding up transmission.

Continuous conduction

The process of action potentials traveling along unmyelinated axons where each voltage-gated ion channel opens and closes in sequence.