Physiology 2130 Lecture Notes - Heart Valve, Sinoatrial Node, Mitral Valve
Document Summary
Chapter 8 notes circulatory system 1: the heart. Origin of self-excitability: two characteristics of sinoatrial node self-excitability. Structure of heart and electrical conducting system. Ecg (electrocardiogram: explain peaks, tell you about health of heart. Cardiac cycle: changes in aortic and ventrical pressure, volume, relate these changes to activity in the valves. Calculate cardiac output and all factors controlling heart rate. Frank-starling law of the heart: how it returns cardiac output to normal. 2 side by side pumps: right atrium/ventricle pump blood to lungs, left atrium/ventricle pump blood to rest of body. Wall of left ventricle thicker than wall of right ventricle. Contracts more forcefully to pump to whole body. Contracts with less force to deliver blood to lungs. Ensure 1 way flow of blood through heart. 2 myocardial cell types in the heart: contractile cells (similar to skeletal, nodal/conducting cells (similar to nerve cells) Contain actin and myosin arranged in microfibrils. The microfibrils are surrounded by sarcoplasmic reticulum.