Neurons, Glial Cells, and Brain Barriers (Intro to Neurobiology)

Vocabulary flashcards covering key concepts from the lecture notes on neurons, glial cells, and the blood-brain barrier.

Neuron

Functional cell of the nervous system that generates and propagates electrical signals (action potentials) and secretes neurotransmitters.

Glial cell

Supportive nervous system cell that insulates neurons, clears waste and excess neurotransmitter, and helps form barriers; roughly equal in number to neurons.

Neuron doctrine

Idea that neurons are discrete, individual cells rather than a continuous net in the brain.

Membrane potential

Voltage difference across a cell’s membrane; neurons change this during signaling.

Resting membrane potential

Baseline membrane voltage of a neuron when it is not firing.

Action potential

Rapid, self-propagating electrical signal that travels along a neuron to convey information.

Excitable cell

Cell capable of changing its membrane potential in response to stimuli (e.g., neurons, muscle cells).

Neurotransmitter

Chemical messenger produced by neurons and released to communicate with target cells.

Neurotransmitter secretion

Release of neurotransmitters from neurons into the synapse or surrounding fluid.

Myelination

Insulation of axons by glial cells to speed transmission and reduce current leakage.

Astrocyte

A type of glial cell involved in regulating the brain environment and forming part of the blood-brain barrier.

Blood-brain barrier

Selective barrier formed by brain capillaries and glial processes that blocks large molecules from entering brain tissue.

Interstital fluid

Fluid surrounding brain cells in which neurotransmitters can diffuse.

Brain cell populations

Two major populations: neurons (functional units) and glial cells (supportive helpers).

Number of brain cells (concept)

Brain contains a large, roughly equal number of neurons and glial cells, each playing different roles in nervous system function.