Heart Mediastinum z z z Mediastinum Anterior Posterior Superior Medisatinum Heart in Situ Heart in Situ z z z z z z Orientation Fibrous Pericardium Parietal Layer of Serous Pericardium Visceral Layer of Serous Pericardium the Epicardium Myocardium The actual heart muscle Serous space frictionless environment 1 Heart Great Vessels z z z z z Pericardium Great Vessels Superior Vena Cava Inferior Vena Cava Pulmonary Trunk pulmonary arteries Pulmonary veins Ascending Aorta Great Vessels Great Vessels 2 Circulation R v L Right Heart v Left Heart z z z z z z Right pulmonary circulation Left systemic circulation Artia right and left holding chambers Ventricles left and right pumping chambers Interventricular septum Thickness of muscular walls Ventricle Walls Right Heart z z z Ventricle Walls Right Heart Right Atrium Sup And Inf Vena Cavae A V orifice Tricuspid valve Anterior Septal Posterior z z Papillary muscles Chordae tendineae 3 Right Heart Right Heart Right A V Tricuspid Right Heart z z z Right Ventricle Pulmonary Valve Semilunar Anterior cusp Right semilunar cusp Left semilunar cusp z Right Ventricle Pulmonary Trunk Right Ventricle 4 Pulmonary Valve Left Heart z z z z Left Atrium A V Orifice Left A V valve Mitral Two primary cusps ant and post Left Atrium Mitral Valve Mitral Valve Left Heart z z Left Ventricle Aortic Valve Right coronary semilunar Left coronary semilunar Posterior semilunar z z Aortic sinuses Openings for right and left coronary arteries 5 Left Ventricle Ascending Aorta z z z z Coronary Circulation z Elastic v distributive arteries Aortic arch Left subclavian and left common carotid Right innominate to right subclavian and right cc Coronary Circulation Left Coronary Artery Anterior Interventricular Circumflex Branch Left Marginal Branch z Right Coronary Artery SA nodal branch Right Marginal Branch Post Interventricular Branch Coronary Circulation Coronary Circulation 6 Coronary Circulation Coronary Circulation Coronary Circulation Coronary Circulation Coronary Circulation Coronary Circulation 7 Conduction System z z z z z z Conducting System SA Node AV Node AV Bundle of His Bundle Branches R and L Purkinjie Fibers Conducting System Innervation of the Heart z Sympathetic z Parasympathetic T1 T4 CN X z z Innervation Cardiac Plexus Circulating Hormones especially from adrenal medulla Blood z z z z 8 of body weight 8 10 pints in females 10 12 pints in men Functions Carries nutrients oxygen hormones and other essentials to cells Removes wastes CO2 Distributes heat maintaining homeostasis at 98 6 F or 37 F Defends body against infection 8 Blood Components of Blood z z z z RBC z z z z z z Plasma 55 90 water 10 solutes WBC and platelets 1 RBC 44 1 drop of blood has 250 million RBC 16 million platelets 375 WBC RBC 25 trillion AKA erythrocytes 99 of cells in blood Vital function of carrying O2 in blood and remove CO2 Produced in marrow of bones at a rate of 2 million per second start off as immature stem cells Single cells can squeeze through capillaries Blood Cells RBC z z z z Are able to carry O2 due to the presence of hemoglobin Each RBC has 250 million hemoglobin molecules that can bind with four O2 molecules meaning that each RBC can bind with 1 billion O2 molecules Hemoglobin is a protein red in color O2 binds readily with hemoglobin so does Carbon Monoxide 9 WBC z z z z z AKA leukocytes Larger than RBC Mobile defense force 375 000 per drop of blood several types of WBC attack specific kinds of invaders from within cancer and without bacteria viruses fungi Two categories granulocytes and agranulocytes lymphocytes and monocytes AKA phagocytes Platelets z z z z z z Clot Produce clotting a self repairing mechanism called Hemostasis Platelets carried by blood congregate around a damage site and form a temporary plug to stop the loss of blood Blood can then coagulate clot to form a more permanent seal When a vessel is damaged the smooth inner lining endothelium of it is damaged and becomes rough this causes platelets to react and clots Blood Vessels z WBC Arteries and Veins Arteries veins and capillaries Arteries have a layer of smooth muscle controlled by the autonomic nervous system not under voluntary control Muscle contraction vasoconstriction can alter the size of the lumen thus affecting the rate of blood movement through it 10 Arteries and Veins Vessels z z z Large vessels become smaller and smaller as they reach target eventually become the capillaries Capillaries become arterioles that allow the diffusion of nutrients across vessel wall to underlying tissue Arterioles overlap with venules which begin the venous journey back to the heart Vessels z z z Veins have little or no muscle wall Depend on muscle contraction to move blood back to heart Veins have valves that prevent backflow Major Arteries z z z z Muscular Pump Aorta ascending arch descending abdominal Carotid common internal external Anterior cerebral middle cerebral Vertebral brain stem vessels posterior cerebral Major Arteries z z Axillary brachial radial ulnar and branches Common iliac external iliac femoral posterior tibial anterior tibial peroneal and branches 11 Lymphatics Lymphatics z z z z z Lymph Vessels and Lymph Organs Maintains blood volume Each day about 51 pints of fluid leaves the blood as it passes through tissues Most returns to capillaries but some 6 8 pints remains Surplus is called lymph drains into lymph vessels and is emptied back into blood stream Lymphatics z z z z Lymph Cappilaries Also plays a major role in body defense mechanism Lymph contains lymphocytes and machrophages Lymph capillaries are found in tissues closely related to arterioles and venules These drain to larger lymphatic vessels that ultimately empty into subclavian veins Organs and Nodes Lymph Organs z z Lymph nodes are found in strategic locations and process lymph passing through it by filtering out pathogens Spleen near the stomach has rich blood supply process incoming blood engulf bacteria viruses worn out RBCs 12 Lymph Organs z z z Thymus near the heart shrinks with age as it is most important in infancy Trains lymphocytes to be effective in immune system as they mature in thymus and become capable of attacking specific pathogens Tonsils back of mouth throat protect the upper GI and respiratory systems from bacteria from air and food 13