Cardiovascular System: The Heart (Chapter 13)

Fun Facts Heart pumps 7,000 liters of blood each day Heart contracts 2.5 billion times in an average lifetime

Heart Hollow, muscular pump Four chambers: R & L Atria – for blood storage R & L Ventricles – to pump blood Posterior to sternum, medial to lungs Anterior to vertebral column Superior to diaphragm

Alveolus Oxygenated blood Deoxygenated blood CO2 O2 Right atrium Right ventricle Left atrium Left ventricle Systemic circuit delivers oxygen to all body cells and carries away wastes. Oxygenated blood pumped to all body tissues via aorta Deoxygenated blood pumped to lungs via pulmonary arteries Pulmonary circuit eliminates carbon dioxide via the lungs and oxygenates the blood. Oxygenated blood returns to heart via pulmonary veins Deoxygenated blood returns to heart via venae cavae

Diaphragm Base of heart Apex of heart Heart Sternum

Coverings of the Heart Pericardium: Fibrous pericardium Auricle of right atrium Right ventricle Pericardial cavity Left ventricle Pulmonary trunk Auricle of left atrium Fibrous pericardium Aorta Right lung Left lung Diaphragm Superior vena cava Anterior interventricular sulcus Heart (covered by visceral pericardium) Cut edge of parietal pericardium Pericardium: Fibrous pericardium Parietal pericardium Visceral pericardium

Wall of the Heart Epicardium (outer layer) Myocardium (middle layer) Endocardium Myocardium Epicardium (visceral pericardium) Pericardial cavity Parietal pericardium Fibrous Coronary blood vessel Wall of the Heart Epicardium (outer layer) Myocardium (middle layer) Endocardium (inner layer)

Wall of the Heart Epicardium (visceral pericardium) forms a protective outer covering and secretes serous fluid Myocardium contracts to pump blood from the heart chambers Endocardium forms a protective inner lining of the chambers and valves

From the Heart to the Lungs Structure Function Right Atrium Chamber where blood enters the heart from the body Receives blood from inferior & superior vena cava, coronary sinus Right Ventricle Receives blood from Right Atrium Pumps blood to the lungs Pulmonary Arteries Carry deoxygenated blood from the heart to the lungs

From the Lungs to the Heart Structure Function Pulmonary Veins Carry oxygenated blood back to the heart from the lungs Left Atrium Receives blood from the pulmonary veins Left Ventricle Pumps blood to the aorta, through the rest of the body Aorta Brings blood from the left ventricle to the vessels of the body

Wall of the Heart Epicardium (outer layer) Myocardium (middle layer) Endocardium (inner layer)

Valves of the Heart Tricuspid valve Pulmonary valve Right atrioventricular orifice Prevents blood from moving back into right atrium during ventricular contraction Pulmonary valve Entrance to pulmonary trunk Prevents blood from moving back into right ventricle during ventricular relaxation

Valves of the Heart Mitral valve Aortic valve Left atrioventricular orifice Prevents blood from moving back into the left atrium during ventricular contraction Aortic valve Entrance to aorta Prevents blood from moving back into left ventricle during ventricular relaxation

Tissue cells Alveolus Left atrium Mitral valve Aortic valve Left ventricle Right atrium Tricuspid valve Pulmonary valve Inferior vena cava Right ventricle Aorta O2 CO2 Systemic capillaries Superior vena cava Alveolar Pulmonary veins artery

Alveolar capillaries (lungs) Blood to systemic circuit Aorta Cardiac veins Coronary sinus Right atrium Right coronary artery Left coronary artery Posterior interventricular artery Marginal Circumflex Anterior Myocardial capillaries in ventricular walls walls of right atrium and right ventricle walls of left atrium and left Tricuspid valve Right atrium Right ventricle Pulmonary trunk Pulmonary arteries Alveolar capillaries (lungs) Pulmonary veins Left atrium Left ventricle Aorta Blood to systemic circuit Pulmonary valve Mitral valve Aortic valve Venae cavae and coronary sinus Blood from systemic circuit

Chambers of the Heart Walls are ridged by pectinate muscles Atria Ventricles Walls are ridged by pectinate muscles Increase the power of contraction without increasing heart mass substantially Papillary muscles & chordae tendinae Prevent backflow of blood Walls are ridged by trabeculae carneae Prevents suction

https://www.youtube.com/watch?v=m_-7e81rVd8