PSYCH 110 Lecture Notes - Lecture 4: University Of Manchester, Nerve Conduction Velocity, Myelin
Document Summary
Ion channels that are normally closed at rest and then open - called voltage gated channels. Na channels open and it rushes in and gets positive. Voltage gated na channels open, gets positive then close. Dendritic spine - dendrite reaches out to action potential, come in different sizes and shapes and can change over time. Found only in axon terminal, closed at neuron rest, action potential, vgcach opens, ca+2 goes in. Calcium triggers the release of vesicles in all different types of cells - so vesicles fused to plasma membrane (exocytosis) and neurotransmitter is released into synaptic cleft. The ca+2 concentration gradient drives ca+2 into the cell. Neurotransmitter binds to receptors (proteins located in postsynaptic cell), receptor does something that causes graded potential. Then transporter takes neurotransmitter and reuptakes it to presynaptic cell. Some have enzyme that degrades neurotransmitter rather than reuptake. Ionotropic receptors: ion channels, na+ comes in, becomes positive inside.
