41) At which corner point of the heart does one listen for the sound of the closing aortic semilunar valve?
A) superior right
B) inferior right
C) superior left
D) inferior left
42) What is the effect of the parasympathetic fibers carried by the vagus nerve?
A) They speed up the heartbeat.
B) They increase the force of cardiac contractions.
C) They slow the heartbeat.
D) The heartbeat is not influenced by the vagus nerve.
43) The crista terminalis can be used to locate all of the following structures
except
the
A) opening of the coronary sinus.
B) opening of the inferior vena cava.
C) opening of the pulmonary veins.
D) opening of the superior vena cava.
44) Which vessel returns most of the venous blood from the heart to the right atrium?
A) the great cardiac vein
B) the coronary sinus
C) the anterior cardiac vein
D) the posterior interventricular vein
45) During ventricular systole, blood is
A) flowing from the systemic and pulmonary circuits into both the atria and ventricles.
B) forced from the atria into the ventricles.
C) forced from the ventricles into the aorta and pulmonary trunk.
D) not flowing into or out of the heart.
46) Blood within the pulmonary veins returns to the
A) right atrium.
B) left atrium.
C) right ventricle.
D) left ventricle.
47) The term for pain caused by deficient blood delivery to the heart wall is
A) ischemia.
B) angina pectoris.
C) myocardial infarct.
D) pericarditis.
48) Stenosis of the mitral valve may cause blood to back up into the
A) venae cavae.
B) pulmonary circulation.
C) right ventricle.
D) coronary circulation.
49) Blood is carried to capillaries in the myocardium by way of the
A) coronary sinus.
B) fossa ovalis.
C) coronary arteries.
D) coronary veins.
50) Which of the following veins does
not
deliver blood directly to the right atrium?
A) superior vena cava
B) inferior vena cava
C) coronary sinus
D) the great cardiac veins