11) Which valve guards the base of the aorta and opens when the ventricles are contracting:

A) mitral valve

B) aortic semilunar valve

C) bicuspid valve

D) pulmonary semilunar valve

E) tricuspid valve

12) Which one of the following are direct branches of the left coronary artery:

A) circumflex and marginal arteries

B) anterior and posterior interventricular arteries

C) anterior interventricular and marginal arteries

D) anterior interventricular and circumflex arteries

E) posterior interventricular and marginal arteries

13) The sinoatrial node is located in the:

A) aorta

B) right atrium

C) left atrium

D) right ventricle

E) interventricular septum

14) Which one of the following represents the correct path for the transmission of an impulse in the intrinsic conduction system of the heart:

A) atrioventricular (AV) node, sinoatrial (SA) node, atrioventricular (AV) bundle, right and left bundle branches, Purkinje fibers

B) atrioventricular (AV) node, atrioventricular (AV) bundle, sinoatrial (SA) node, Purkinje fibers, right and left bundle branches

C) sinoatrial (SA) node, atrioventricular (AV) bundle, atrioventricular (AV) node, Purkinje fibers, right and left bundle branches

D) sinoatrial (SA) node, atrioventricular (AV) bundle, atrioventricular (AV) node, right and left bundle branches, Purkinje fibers

E) sinoatrial (SA) node, atrioventricular (AV) node, atrioventricular (AV) bundle, right and left bundle branches, Purkinje fibers

15) Chest pain resulting from the loss of oxygen to heart cells is called:

A) endocarditis

B) angina pectoris

C) stroke

D) myocardial infarction

E) heart block

16) Which of these events is NOT associated with ventricular systole:

A) atrioventricular valves close

B) heart is relaxed

C) blood rushes out of the ventricles

D) pressure in ventricles rises

E) semilunar valves open

17) The mitral valve is normally closed:

A) when the ventricle is in diastole

B) when the ventricle is in systole

C) when the atrium is contracting

D) by the movement of blood from the atrium to the ventricle

E) when the ventricle is contracting

18) A person with a heart rate of 75 beats per minute and a stroke volume of 60 mL per beat has a cardiac output of:

A) 4500 mL/minute

B) 1.25 mL/minute

C) 0.8 mL/minute

D) 6000 mL/minute

E) 120 mL/minute

19) Which one of the following is true concerning the “lub-dup” sounds of the heart:

A) the first sound is longer and louder and is caused by closure of the tricuspid valve; the second sound is shorter and sharper and is caused by closure of the mitral valve

B) the first sound is shorter and sharper and is caused by closure of the tricuspid valve; the second sound is longer and louder and is caused by closure of the mitral valve

C) they are caused by contraction of the ventricles, followed by contraction of the atria

D) the first sound is longer and louder and is caused by closure of the AV valves; the second sound is shorter and sharper and is caused by closure of the semilunar valves

E) the first sound is shorter and sharper and is caused by closure of the semilunar valves; the second sound is longer and louder and is caused by closure of the AV valves

20) The volume of blood pumped out by each ventricle with each beat of the heart is called the:

A) cardiac output

B) cardiac cycle  

C) stroke volume

D) heart rate

E) diastolic pressure