1. 16-17 March 2015 What questions do you have about the heart?

2. What is the major function of the cardiovascular system? To transport materials (oxygen, nutrients, wastes, hormones, immune components, heat, etc.) throughout the body What is the heart’s role in this system, and what are the other major components? Heart is the pump – supplies the force to move the blood. Blood carries the materials Vessels are roads and exchange surfaces

4. Pericarditis is inflammation of the pericardium.

5. Cardiac vessels supply the heart muscle itself with blood. Heart disease (atherosclerosis) occurs when the aorta or cardiac arteries become clogged with fatty plaques.

7. The right side of the heart receives oxygen-poor blood from the body and pumps it to the lungs  pulmonary circulation The left side of the heart receives oxygen-rich blood from the lungs and pumps it to the body  systemic circulation

8. Each side has an atrium for collecting blood and a ventricle for pumping blood to the lungs or body Blood collects in atria while ventricles contract. Then, as ventricles relax, atria contract slightly and ventricles refill. Two sides of heart contract and relax simultaneously.

9. Use the diagram to determine the flow of blood through the heart and body. Vena cava       Vena cava R. atrium R. ventricle Pulmonary artery Lung vessels Pulmonary vein L. atrium L. ventricle aorta Body vessels

10. The walls of the ventricles are much thicker than that of the atria? Why? Ventricles are more muscular, since they are the major pumps. Look at the diagram – how does the left ventricle differ from the right? What is the reason for the difference? Left ventricle is more muscular – needs to pump blood throughout entire body, while right ventricle just needs to send blood to lungs.

11. Atrioventricular valves (tricuspid and mitral) hang open when the ventricles are filling forced closed when the ventricles contract anchored by chordae tendineae AV valves prevent backflow from __________________ to __________________

12. Atrioventricular valves (tricuspid and mitral) hang open when the ventricles are filling forced closed when the ventricles contract anchored by chordae tendineae Semilunar valves (pulmonary and aortic) forced open when ventricles contract closed when ventricles relax AV valves prevent backflow from ventricles to atria SL valves prevent backflow from ________ to__________

13. Atrioventricular valves (tricuspid and mitral) hang open when the ventricles are filling forced closed when the ventricles contract anchored by chordae tendineae Semilunar valves (pulmonary and aortic) forced open when ventricles contract closed when ventricles relax AV valves prevent backflow from ventricles to atria SL valves prevent backflow from arteries to ventricles

14. In what stage of the cardiac cycle is the heart shown below? How do you know? Ventricles are contracting (in systole) because SL valves open (and AV valves close) when ventricles contract to force blood only towards arteries. Atria are relaxed (in diastole) Where else have you heard these words?

15. Normal hearts make the sound: LUB-dup LUB-dup LUB-dup The “LUB” is caused by the closing of the AV valves. The “dup” is caused by the closing of the semilunar valves. Heart murmurs are abnormal heart sounds. In children, these are often benign. In adults, they usually indicate a problem – often, the failure of the valves to work properly. Why is it a problem if the valves don’t function properly? Mitral valve murmur Aortic stenosis murmur

17. What questions did we answer today? What haven’t we answered? What new questions do you have? HOMEWORK Wed / Thursday – Present answers to questions Friday / Monday – Review Exercise 20 Quiz next Wednesday or Friday