Chapter 20, part 4Factors Affecting Heart RateFigure 20.20 Factors Affecting Cardiac OutputMedulla Oblongata centers affect autonomic innervationFigure 20.21 Autonomic Innervation of the HeartSlide 6Basic heart rate established by pacemaker cellsFigure 20.22 Pacemaker FunctionSlide 9Factors Affecting stoke volumeFigure 20.23 Factors Affecting Stroke VolumeSlide 12Autonomic ActivityExercise and Cardiac OutputSummary: Regulation of Heart Rate and Stroke VolumeFigure 20.24 A Summary of the Factors Affecting Cardiac OutputSECTION 20-5 The Heart and the Cardiovascular SystemThe heart is part of the cardiovascular systemYou should now be familiar with:Slide 20Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Fundamentals of Anatomy & PhysiologySIXTH EDITIONFrederic H. MartiniPowerPoint® Lecture Slide Presentation prepared by Dr. Kathleen A. Ireland, Biology Instructor, Seabury Hall, Maui, HawaiiChapter 20, part 4The HeartCopyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings•Autonomic innervation•Cardiac reflexes•Tone•SA node•Hormones•Epinephrine (E), norepinephrine(NE), and thyroid hormone (T3) •Venous returnFactors Affecting Heart RateCopyright © 2004 Pearson Education, Inc., publishing as Benjamin CummingsFigure 20.20 Factors Affecting Cardiac OutputFigure 20.20Copyright © 2004 Pearson Education, Inc., publishing as Benjamin CummingsMedulla Oblongata centers affect autonomic innervation•Cardioacceleratory center activates sympathetic neurons•Cardioinhibitory center controls parasympathetic neurons•Receives input from higher centers, monitoring blood pressure and dissolved gas concentrationsCopyright © 2004 Pearson Education, Inc., publishing as Benjamin CummingsFigure 20.21 Autonomic Innervation of the HeartFigure 20.21Copyright © 2004 Pearson Education, Inc., publishing as Benjamin CummingsFigure 20.21 Autonomic Innervation of the HeartFigure 20.21Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings•SA node establishes baseline•Modified by ANS•Atrial reflexBasic heart rate established by pacemaker cellsCopyright © 2004 Pearson Education, Inc., publishing as Benjamin CummingsFigure 20.22 Pacemaker FunctionFigure 20.22Copyright © 2004 Pearson Education, Inc., publishing as Benjamin CummingsFigure 20.22 Pacemaker FunctionFigure 20.22Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings•EDV•Frank-Starling principle•ESV•Preload•Contractility•AfterloadFactors Affecting stoke volumeCopyright © 2004 Pearson Education, Inc., publishing as Benjamin CummingsFigure 20.23 Factors Affecting Stroke VolumeFigure 20.23Copyright © 2004 Pearson Education, Inc., publishing as Benjamin CummingsFigure 20.23 Factors Affecting Stroke VolumeFigure 20.23Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings•Sympathetic stimulation •Positive inotropic effect•Releases NE •Parasympathetic stimulation•Negative inotropic effect•Releases AChAutonomic ActivityCopyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings•Heavy exercise can increase output by 300-500 percent•Trained athletes may increase cardiac output by 700 percent•Cardiac reserve •The difference between resting and maximal cardiac outputExercise and Cardiac OutputAnimation: Cardiac cyclePLAYCopyright © 2004 Pearson Education, Inc., publishing as Benjamin CummingsSummary: Regulation of Heart Rate and Stroke Volume•Sympathetic stimulation increases heart rate•Parasympathetic stimulation decreases heart rate•Circulating hormones, specifically E, NE, and T3, accelerate heart rate•Increased venous return increases heart rate•EDV is determined by available filling time and rate of venous return•ESV is determined by preload, degree of contractility, and afterloadCopyright © 2004 Pearson Education, Inc., publishing as Benjamin CummingsFigure 20.24 A Summary of the Factors Affecting Cardiac OutputFigure 20.24Copyright © 2004 Pearson Education, Inc., publishing as Benjamin CummingsSECTION 20-5 The Heart and the Cardiovascular SystemCopyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings•The goal of the cardiovascular system is to maintain adequate blood flow to all body tissues•The heart works in conjunction with cardiovascular centers and peripheral blood vessels to achieve this goalThe heart is part of the cardiovascular systemCopyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings•The organization of the cardiovascular system. •The location and general features of the heart, including the pericardium.•The differences between nodal cells and conducting cells as well as the components and functions of the conducting system of the heart.•The electrical events associated with a normal electrocardiogram.You should now be familiar with:Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings•The events of the cardiac cycle including atrial and ventricular systole and diastole, and the heart sounds related to specific events in the cycle.•Cardiac output, heart rate and stroke volume and the factors that influence these variables.•How adjustments in stroke volume and cardiac output are coordinated at different levels of activity.You should now be familiar