EGRB 111 Class 33: Ion Channels and Membrane Potential

Vocabulary flashcards for ion channels and membrane potential

Membrane Potential

The charge difference (measured in Volts) between the inside and outside of the cell.

Mechanically-gated Ion Channel

Ion channels that are physically stretched open.

Ligand-gated Ion Channel

Ion channels that open when a ligand binds to the channel.

Voltage-gated Ion Channel

Ion channels that change their opening frequency based on the voltage difference across the cell.

Dendrite

Branchlike parts of a neuron that are specialized to receive information.

Axon

A long, slender projection of a nerve cell, or neuron, that typically conducts electrical impulses away from the neuron's cell body.

Nerve Terminal

The location where the axon of one neuron makes contact with another neuron or with an effector cell (muscle or gland).

Action Potential

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

Synapse

A structure that permits a neuron (or nerve cell) to pass an electrical or chemical signal to another neuron or to the target effector cell.

Synaptic Cleft

The space between neurons at a nerve synapse across which a nerve impulse is transmitted by a neurotransmitter.

Synaptic Vesicle

A small bubble-like structure in the presynaptic terminal that contains neurotransmitters.

Neurotransmitter

A chemical substance that is released at the end of a nerve fiber by the arrival of a nerve impulse and, by diffusing across the synapse or junction, causes the transfer of the impulse to another nerve fiber, a muscle fiber, or some other structure.

Excitatory vs Inhibitory Neurons

Neurons that either activate the neuron or make it harder for the neuron to activate