PSYC*3150 Lecture Notes - Lecture 2: Axon Terminal, Myelin, Membrane Potential
Document Summary
Neurons: individual nerve cells that are basic building blocks of the nervous system. Not all axons are covered in a myelin sheath (speed up rate of action potential) When the neuron is at rest, the concentration of positively charged sodium ions is greater outside the axon membrane whereas negatively charged protein and chloride ions are concentrated within the axon (-70mv) When the neuron is stimulated, certain ion channels open, permitting positive ions into the axon , and some depolarization of the axon will occur - it is an all or none. Stimulation high enough = threshold of excitation reached, and depolarization. Is the junction between two neurons - is generally separated by a gap called the synaptic cleft. When an action potential reaches the axon terminal, neurotransmitters (nts) stored in the terminal button are released into the synapse. Nts trigger activity in the adjacent neuron.
