PSYB65H3 Lecture Notes - Lecture 4: Neurotransmitter Receptor, Acetyl-Coa, Axon Terminal
Document Summary
When action potential goes past the threshold, na channels open and lots of sodium enters the neuron and neuron fires. Action potential: large positive charge across the neural membrane, caused by sodium influx. Info travels down the axon until the synaptic terminal button which meets w a dendrite of the next neuron. Junction = synapse; space in between is the synaptic cleft. Synaptic vesicles get released from presynaptic axon when action potential hits fuse w the membrane and empty transmitter substance contents into synaptic cleft. Transmitter interacts w receptors on the postsynaptic membrane of dendrite => cause channels to open, allow na to enter and continues the action potential. In order to transmit information transmitter needs to interact, but needs to be quickly inactivated so that a different signal can come in. Chemicals in the synaptic cleft exist to breakdown transmitters.