Circulation The blood mobile https go wisc edu ga9byp Animal Cardiovascular Systems Lecture 11 Circulatory system is incredible Your CS must reach every cell in your body 30 40 trillion cells in your body FYI there are 10x that in bacteria Pumps 2 000 gallons a day through your heart 5 6 quarts of blood in your body Pumping 2 000 gallons day using 5 6 quarts requires an extensive network of blood vessels under close control Capillary bed Vein Artery structure f x Venule Arteriole Capillary Valve Lumen Endothelium Elastic layer Smooth muscle Elastic layer Epithelium Artery Vein Arteries vs Veins Oxygenated Red Blood AWAY from the heart Low volume 10 15 High pressure Deoxygenated Blue blood TOWARDS the heart High volume 65 70 Low pressure Pressure vs Resistance Resistance R to blood flow Viscosity constant Distance traveled length longer the vessel R Vessel radius r R 1 r4 Rate of flow P R Pressure P required to overcome R Aorta Arteries and Capillaries arterioles Venules and veins Vessel Area vs Flow Velocity l a n o i t c e s s s o r c l a t o T 2 m c a e r a r a e n i l n a e M y t i c o e v l s m c Blood pressure Osmotic pressure 32 mmHg Net pressure out Blood pressure Osmotic pressure Net pressure in Interstitial fluid 10 mmHg 15 mmHg Ins Outs of capillaries Blood Flow 9 mmHg 22 mmHg 24 mmHg Arterial end of capillary Venous end of capillary 20L of fluid and stuff exits your capillaries day 17L of which is returned what happens to the rest Lymphatic system Lymph what even is it Whatever squeezes out b n the cells in your capillaries Water proteins small minerals Lymphocytes Vessels similar in structure to veins Ducts drain vessels Nodes collection points filled with immune cells Lung capillaries Mammalian Heart and Circulatory System Pulmonary circulation Systemic circulation 4 chambered heart Increases O2 to active Increases O2 uptake in tissues lungs Heart Systemic capillaries Mammalian Heart and Circulatory System Superior vena cava Arteries to head and arms Aorta Right pulmonary artery Right atrium Right pulmonary veins Right AV valve Right ventricle Inferior vena cava Pulmonary valve Left pulmonary artery Left atrium Left pulmonary veins Left AV valve Aortic valve Left ventricle Cardiac muscle Think Write Share We know that the more force a muscle can generate depends upon the amount of muscle contracting Which chambers in the heart require more muscle to deliver their blood to where it is going The atria or the ventricles Which atria requires more muscle Which ventricle Mammalian Heart contractions pressures valves 1 Deoxygenated blood enters the right atrium from the inferior and superior venae cava Deoxygenated blood passes through the right AV valve and enters the right ventricle 2 3 Deoxygenated blood is pumped into the pulmonary arteries through the pulmonary valve 6 3 4 1 2 5 4 Oxygenated blood returns from the lungs to the left atrium 5 6 Oxygenated blood enters the left ventricle through the left AV valve Oxygenated blood is pumped by the left ventricle through the aortic valve into the systemic circulation Deoxygenated blood enters the right atrium from the inferior and superior venae cava Deoxygenated blood passes through the right AV valve and enters the right ventricle Deoxygenated blood is pumped into the pulmonary arteries through the pulmonary valve Oxygenated blood returns from the lungs to the left atrium Oxygenated blood enters the left ventricle through the left AV valve Oxygenated blood is pumped by the left ventricle through the aortic valve into the systemic circulation Diastole Systole Cardiac Cycle In diastole the atria contract filling the ventricles with blood In systole the ventricles contract pumping blood out of the heart In diastole the atria contract filling the ventricles with blood In systole the ventricles contract pumping blood out of the heart Coordinating Heartbeat with Action Potentials via Gap Junctions SA node pacemaker AV node Modified muscle fibers Purkinje Heartbeat Depolarization Process 1 The pacemaker generates action potentials that spread through both atria They contract in unison 2 The signals from the pacemaker reach the AV node which activates and fires 3a The action potentials are transmitted through a set of modified muscle fibers 3b The depolarization spreads from the modified muscle fibers through the entire ventricle The ventricles contract SA node pacemaker AV node Sympathetic stimulation speeds up heart rate Parasympathet ic stimulation slows down heart rate Modified muscle fibers The pacemaker generates action potentials that spread through both atria They contract in unison The signals from the pacemaker reach the AV node which activates and fires The action potentials are transmitted through a set of modified muscle fibers The depolarization spreads from the modified muscle fibers through the entire ventricle The ventricles contract Sympathetic stimulation speeds up heart rate Parasympathetic stimulation slows down heart rate Electrocardiogram EKG 3b 3a 2 1 The pacemaker generates action potentials that spread through the atria They contract in unison The signals from the pacemaker reach the AV node which activates and fires The action potentials are transmitted through a set of modified muscle fibers The depolarization spreads from the modified muscle fibers through the entire ventricle The ventricles contract SA node pacemaker AV node Sympathetic stimulation speeds up heart rate Parasympathetic stimulation slows down heart rate EKG Electrocardiograms EKGs show when 1 the SA node is activated and the atria contract 2 the AV node is activated and 3 the ventricles contract Afterward the ventricles repolarize and relax Modified muscle fibers SA node activated atria contract AV node activated Ventricles contract The pacemaker generates action potentials that spread through the atria They contract in unison The signals from the pacemaker reach the AV node which activates and fires The action potentials are transmitted through a set of modified muscle fibers The depolarization spreads from the modified muscle fibers through the entire ventricle The ventricles contract Electrocardiograms EKGs show when 1 the SA node is activated and the atria contract 2 the AV node is activated and 3 the ventricles contract Afterward the ventricles repolarize and relax SA node activated atria contractAV node activatedVentricles contractSympathetic stimulation speeds up heart rate Parasympathetic stimulation slows down heart rate