Heart Part 1

16. Which of the following carry oxygen-poor blood? A. Pulmonary veins and vena cavae B. Aorta and pulmonary veins C. Aorta and vena cavae D. Venae cavae and pulmonary arteries E. Pulmonary veins and pulmonary arteries

17. Which of the following belong to the pulmonary circuit? A. Aorta and venae cavae B. Aorta and pulmonary veins C. Pulmonary arteries and venae cavae D. Venae cavae and pulmonary veins E. Pulmonary arteries and pulmonary veins

18. Which of the following is the most superficial layer enclosing the heart? A. Parietal pericardium B. Visceral pericardium C. Endocardium D. Epicardium E. Myocardium

19. The heart is located in the space called the __________. A. pericardial cavity B. mediastinum C. abdominal cavity D. pleural cavity E. myocardium

20. The apex of the heart is found __________ of the midline of the body. A. to the right B. to the left C. in the center

21. Pericardial fluid is found between the __________ and the __________. A. visceral pericardium; myocardium B. visceral pericardium; epicardium C. parietal; visceral membranes D. myocardium; endocardium E. epicardium; myocardium

22. The __________ are the superior chambers of the heart and the _________ are the inferior chambers of the heart. A. visceral percardia; parietal pericardia B. ventricles; atria C. atria; ventricles D. left ventricles; right ventricles E. left atria; right atria

23. The shallow depression seen on the external surface of the heart between the left and right ventricles is called the __________. A. coronary sinus B. interventricular sulcus C. interventricular septum D. coronary sulcus E. left atrium

24. The area where the major vessels lead to and from the heart's chambers is called the __________ of the heart. The pointy, inferior portion is called the ___________. A. apex; base B. atrium; ventricle C. ventricle; atrium D. base; apex E. endocardium; epicardium

25. The __________ performs the work of the heart. A. fibrous skeleton B. pericardial cavity C. endocardium D. myocardium E. epicardium

26. The right atrioventricular valve (tricuspid) regulates the opening between the _________ and the _________. A. right atrium; left atrium B. right atrium; right ventricle C. right atrium; left ventricle D. left atrium; left ventricle E. left ventricle; right ventricle

27. Oxygen-poor blood passes through the _________. A. right AV (tricuspid) and pulmonary valves B. right AV (tricuspid) valve only C. left AV (mitral) and aortic valves D. left AV (mitral) valve only E. pulmonary and aortic valves

28. Opening and closing of the heart valves is caused by _________. A. breathing B. gravity C. valves contracting and relaxing D. osmotic gradients E. pressure gradients

29. The __________ valve regulates the flow of blood between the right ventricle and the vessels leading to the lungs. A. right atrioventricular B. left atrioventricular C. aortic D. pulmonary E. mitral

30. The __________ carry blood toward the lungs. A. pulmonary arteries and veins B. pulmonary trunk and arteries C. pulmonary trunk and veins D. superior and inferior venae cavae E. aorta and pulmonary arteries

31. Which of the following blood vessels receives blood directly from the right ventricle? A. Pulmonary trunk B. Ascending aorta C. Superior vena cava D. Inferior vena cava E. Right pulmonary vein

32. The chordae tendinae of the AV valves are anchored to the __________ of the ventricles. A. papillary muscles B. pectinate muscles C. trabeculae carnae D. interventricular septum E. interatrial septum

33. After entering the right atrium, the furthest a red blood cell can travel is the _________. A. right ventricle B. pulmonary trunk C. superior vena cava D. ascending aorta E. left atrium

34. Which of the following directly stems from the ascending aorta before it branches into the circumflex branch and anterior interventricular branch? A. Right coronary artery B. Great cardiac vein C. Right coronary vein D. Left coronary artery E. Left coronary vein

35. Obstruction of the ___________ will cause a more severe myocardial infarction (MI) than the obstruction of any of the others. A. left marginal vein B. left coronary artery (LCA) C. posterior interventricular vein D. anterior interventricular branch E. circumflex branch

36. Which of the following is a feature shared by cardiac muscle and skeletal muscle? A. Muscle fiber striations B. Dependence upon nervous stimulation C. Communication via electrical (gap) junctions D. Intercalated discs E. Autorhythmicity

37. The __________ is the pacemaker that initiates each heart beat. A. sympathetic division of the nervous system B. autonomic nervous system C. sinoatrial (SA) node D. atrioventricular (AV) node E. cardiac conduction system

38. Which of the following is not part of the cardiac conduction system? A. Sinoatrial (SA) node B. Tendinous cords C. Atrioventricular (AV) node D. Atrioventricular (AV) bundle (bundle of His) E. Purkinje fibers

39. Which of the following is not a feature of cardiac muscle? A. They depend almost exclusively on aerobic respiration. B. They are rich in glycogen. C. They have larger than average mitochondria. D. They are very rich in myoglobin. E. They have about the same endurance as skeletal muscle fibers.

40. Which is the correct path of an electrical excitation from the pacemaker to a cardiocyte in the left ventricle (LV)? A. Sinoatrial (SA) node atrioventricular (AV) bundle atrioventricular (AV) node Purkinje fibers cardiocyte in LV B. Atrioventricular (AV) node Purkinje fibers atrioventricular (AV) bundle sinoatrial (SA) node cardiocyte in LV C. Atrioventricular (AV) node sinoatrial (SA) node atrioventricular (AV) bundle Purkinje fibers cardiocyte in LV D. Sinoatrial (SA) node atrioventricular (AV) node atrioventricular (AV) bundle Purkinje fibers cardiocyte in LV E. Sinoatrial (SA) node atrioventricular (AV) node Purkinje fibers atrioventricular (AV) bundle cardiocyte in LV

41. The pacemaker potential is a result of _________. A. Na+ inflow B. Na+ outflow C. K+ inflow D. K+ outflow E. Ca2+ inflow

42. The plateau in the action potential of cardiac muscle results from the action of __________. A. Na+ inflow B. K+ inflow C. K+ outflow D. fast Ca2+ channels E. slow Ca2+ channels

43. When sodium channels are fully open, the membrane of the ventricular cardiocyte _________. A. sharply hyperpolarizes B. sharply repolarizes C. sharply depolarizes D. plateaus E. has no reponse

44. Cells of the sinoatrial node __________ during the pacemaker potential. A. depolarize fast B. depolarize slow C. repolarize slow D. repolarize fast E. depolarize slow and repolarize fast

45. Any abnormal cardiac rhythm is called a(n) __________. A. ectopic focus B. sinus rhythm C. nodal rhythm D. heart block E. arrhythmia