40. Action Potentials and Synapses

In this lecture, we review the initiation of action potentials and discuss how the anatomy of the neuron allows action potentials to propagate along the axon. Once a depolarization arrives at the axon terminal, the synapse provides a mechanism for an action potential in one neuron to depolarize another neuron, giving the nervous system its information- transmitting capability. We then examine the structure and function of synapses and neurotransmitters, the chemical signals found at synapses. Finally, we use this information to reexamine the physiological basis of common nervous system activities.