PHYL2001 Study Guide - Final Guide: Electrical Resistance And Conductance, Pacemaker Potential, Chronotropic
Document Summary
Describe conduction of electrical signals through heart. Describe origin of heart beat, and actions of autonomic neurotransmitters. De ne atrioventricular and semilunar valves (av and sl valves) Ap coordinate activation of contraction of heart. Electrical signalling is important in muscle, nerves and heart. They are changed to positive when electrical impulses run through. Electrical signals (neurotransmitters) are fast, chemical signals slower. Electrical signals can travel fast in long distance. Unlike hormones: slower but does dissipate as quick. Gap junctions allow cardiac ap to propagate from cell to cell through low. (all cardiac cells are connected to each other, unlike skeletal) Skeletal cells have di erent insertion point hence they are not connected to one another. So that when contract, they pull each other. When physically pull onto each other, they can electrically spread signals to each other. When one of them produce ap, it will spread via gap junction. Important: spread electrical impulses with low electrical resistance pathway.
