PS101 Lecture Notes - Lecture 3: Myelin, Schwann Cell, Neuroglia
Document Summary
Neurons: cells specialized in carrying information through the nervous system. Cell body: integrated synaptic information and transmits it to other cells. Dendrites: receive information from other neurons and sensory receptors. Axons: carry neron messages to terminal buttons, form the tail. Myelin sheath: type of glia cell, covers segments of the axon to insulate and speed neural processes. Nodes of ranvier: gaps where information could be lost. Terminal buttons: form junctions with other cells and release neurotransmitters. Astroglia: shaped like stars, create the blood-brain barrier, regulate flow of blood, increase/decrease neuron activity. Absorb and clean up chemicals released by neighbouring neurons. Action potential: stimulated, channels in membrane open, + vely charged sodium ions enter, shift in electrical charge. Intensity is converted by rapidity of firing (rapid firing neurons vs. slow firing neurons) Ie: when you consume some drugs, neurotransmitters fire differently, but no neurons ever go off all at the same time or we would not have coordinated motion.
