Presentation on theme: "Heart Objectives Describe the location and surface anatomic"— Presentation transcript:
1Heart Objectives Describe the location and surface anatomic features of the heartCompare and contrast the two major circulatory systems in the human bodyDiagram, without reference to your notes or book, the path of blood flow through the heart and lungsIdentify the major blood vessels, chambers and valves of the heart
2Systemic Circulation–Carries oxygenated blood from the aorta to the tissuesthe left ventricle ejects blood into the aortaThe blood is distributed to 6 majororgan systems: brain, heart, kidneys,muscle, GI system, and skinThe circulatory system is often describedas a “tree”– Blood vessels are arranged in parallel
3The Pulmonary Circulation the pulmonary circulation carriesdeoxygenated blood (venous blood) tothe lungs and then back to the heartthe right ventricle ejects blood into thepulmonary circulationblood leaving the pulmonary circuit(arterial blood) enters the left atrium
5Summary Pulmonary circulation: Path of blood from right ventricle through the lungs and back to the heart.Systemic circulation:Oxygen-rich blood pumped to all organ systems to supply nutrients.Rate of blood flow through systemic circulation = flow rate through pulmonary circulation.
9The Cardiac Outputthe amount of blood pumped by the ventricles per unit timeunder resting conditions, the left and right ventricles each pump about 5 liters of blood per minutethis value can be increased to as much as 30 liters per minute during maximal exercise
10Superficial Anatomy of the Heart the heart is located behind the sternum, above the diaphragm2/3 of the mass lies left of midline, and the apex points down and to the left.the heart is about 5 inches long, 3.5 inches wide and 2.5 inches thickthe great vessels that emerge from the heart include the pulmonary arteries and veins, the aorta, and the superior and inferior vena cava.
11Chambers of the Heart The mammalian heart is composed of four chambers – the right atrium– the left atrium– the right ventricle– the left ventricle• the left ventricle has much more muscle andis much thicker than the right ventricle
12Note: wall of left ventricle is thicker than right ventricle
13Heart Valves the heart has four “one-way” valves The valves insure that the blood flows in onedirection, from heart to tissues and back to the hearttwo atrioventricular valves (between atria andventricles)two semilunar valves (between LV and aortaand between RV and pulmonary trunk)
15Atrioventricular Valves the left AV valve is also called the bicuspid or mitral valve, and separates the left atrium and left ventriclethe right AV valve is also called the tricuspid valve, and separates the right atrium and right ventricle
17Semilunar ValvesThe aortic semilunar valve separates the left ventricular chamber from the aorta.the pulmonary semilunar valve separates theright ventricular chamber from the main pulmonary trunk.these valves are pressure dependent, meaning that they open and close in response to pressure differences in the vessels and ventricular chambers.
18Pressure-dependent Valve Function Aortic Pressure = 90 mmHgVentricular Pressure =85 mmHg;valves closed andblood is not ejectedAortic Pressure = 100 mmHgVentricular Pressure =101 mmHg;valves open andblood is ejected
19Blood Supply to Heart Muscle the tissues of the heart are supplied with blood from the right and left coronary arteriesthe right coronary artery originates onthe ascending aortathe left coronary artery also originateson the ascending aorta