neurobiology chapter 5 vocab

Electrical synapse

A synapse in which electrical current flows directly from one cell to another via gap junction.

Chemical synapse

A synapse in which presynaptic activity stimulates the release of neurotransmitter, which activates receptors in the postsynaptic membrane

Gap Junction

A specialized junction with a narrow gap between two cells is spanned by protein channels (connexons) that allows ions to pass directly from one cell to another

Secretory granute

A spherical membrane-enclosed vesicle about 100nm in diameter containing peptides intended for secretion by exocytosis, also called dense core vesicles

Active Zone

A pre-synaptic Membrane differentiation that is the site of neurotransmitter release.

Postsynaptic density

A postsynaptic memory differentiation that is the site of Neurotransmitter receptors

Neuromuscular junction

A chemical synapse between a Spinal motor neuron axon and a skeletal Muscle fiber.

Exocytosis

The process whereby material is released from an extra vesicle into the extra cellular space by fusion of the vesicle membrane in the cell membrane

Endocytosis

The process by which a bit of the cell membrane Is pinched off, internalized, and converted to an intracellular vesicle

Transmitter gated by ion-channels

A membrane forming a pore that is permeable to ions and gated by neurotransmitter

Excitatory post-synaptic potential

Depolarization of the postsynaptic membrane potential by the action of a synaptically released neurotransmitter

Inhibitory post-synaptic potential

A change in the postsynaptic membrane potential by the action of a synaptically released neurotransmitter, making the postsynaptic neuron less likely to fire action potentials

G-protein coupled receptor

A membrane protein that activates G-proteins when it binds neuron transmitters.

Autoreceptor

A receptor in the membrane of the presynaptic axon terminal that is sensitive to the neurotransmitter released by the terminal

Spatial summation

The combining of excitatory postsynaptic potentials generated at more than one synapse on the same cell

Temporal summation

The combining of excitatory postsynaptic generated in rapid succession at the same synapse

Neuropharmacology

The study of the effects of drugs on nervous system tissue

Inhibitor

A drug or toxin that blocks the normal action of a protein or a biochemical process.

Receptor antagonist

A drug that binds to a receptor and inhibits its function

Receptor agonist

A drug that binds to a receptor and activates it