3. Aristotle

5. Galen of Pergamum and Pneuma Zoticon

7. DaVinci

8. WILLIAM HARVEY (1628)

9. How has the actual anatomy of the heart changed over time?

10. Open v. Closed Circulatory System OPEN Pro: Simple Con: Low Efficiency CLOSED Pro: High Efficiency Con: Complex Needs

11. Why Are Massive Insects Not Possible? Size of organism limited by type of circulatory system Large organisms cannot survive with open circulatory system due to limitations of the pumping apparatus

13. Evolution of The Heart Trend towards increased separation of oxygenated and deoxygenated blood Increased separation of blood facilitates increased activity, terrestrial lifestyle and homeothermic regulation

21. The Human Heart At Work 72 contractions/min = 2.5 billion/lifetime 60,000 miles/day 1.5 million gallons/lifetime Enough energy expended in a lifetime to drive a pickup truck to the moon and back

24. Orientation of Heart Size of fist? Depends upon age and health Apex of heart (inferior tip) is just superior to the diaphragm at the lower end of the thoracic cavity Heart points sinister and 2/3rds of heart mass is sinister to the midline

25. Pericardium Covers and nourishes the myocardium Serous fluid-lubricates heart/reduces friction

27. Anatomy of the Heart Wall Epicardium-Parietal layer of pericardium Myocardium – made of intercalated cardiomyocytes Endocardium-made of epithelial (skin) cells that prevent blood from sticking to inner wall (clotting)

29. Myocardial Thickness Right Side = thin Blood only pumping to lungs or right ventricle Left side = thick Blood pumped to systemic circulation and extremities

31. Atria (Auricles) Left Atrium Receives deoxygenated blood from body via vena cava Right Atrium Receives oxygenated blood from lungs via pulmonary vein/valve

33. Ventricles Right Ventricle Receives blood from right atrium Left Ventricle Receives blood from left atrium

34. Ventricular Septum Separates right and left ventricle Prevents mixing of oxygenated and deoxygenated blood

36. Cardiac Valves Function: to prevent the backwards flow of blood through coronary circulation

37. Atrioventricular Valves Tricuspid Valve Separates right atrium from right ventricle Bicuspid (Mitral) Valve Separates left atrium from left ventricle

38. Chordae Tendinae Cordis Tendons that open and shut the tricuspid and bicuspid valves Attached to leaflets (valve flaps) and anchored to epicardium covering the papillary muscles

39. Mitral Valve Prolapse Chordae tendinae fail to close the leaflets of the bicuspid valve Blood regurgitates from the left ventricle back into the left atrium

40. Semilunar Valves Crescent shaped cusps Lack Chordae Tendinae/Closed by Blood Pressure Alone Valves located on structures ejecting blood away from the heart Pulmonary Semilunar Valve = right atrium Aortic Semilunar = left atrium

42. Coronary Circulation