31) The superior corner of the right atrium of the heart is located at the
A) costal cartilage of the sixth rib, a finger's width lateral to the sternum.
B) costal cartilage of the third rib where it attaches to the sternum.
C) fifth intercostal space along a line extending inferiorly from the midpoint of the clavicle.
D) midpoint of the jugular notch.
32) The auricles are
A) earlike flaps on the surface of the ventricles.
B) earlike flaps on the surface of the atria.
C) projections of the endothelium into the ventricles.
D) modifications of the pectinate muscles on the inner surface of the atria.
33) What structures anchor the chordae tendineae?
A) trabeculae carneae
B) papillary muscles
C) pectinate muscles
D) semilunar valves
34) Which structure develops from the embryological chamber called the bulbus cordis?
A) the left atrium
B) the right ventricle
C) the left ventricle
D) the sinoatrial node
35) Which of the following structures is
not
found in the left ventricle?
A) the pectinate muscles
B) the mitral valve
C) the trabeculae carneae
D) the papillary muscles
36) The right ventricle pumps blood into which vessel?
A) the aorta
B) the pulmonary vein
C) the pulmonary trunk
D) the superior vena cava
37) A drop of blood returning to the heart from the head region would enter the heart through which vessel?
A) a pulmonary vein
B) the inferior vena cava
C) the superior vena cava
D) the coronary sinus
38) The cusps of the valves of the heart are covered by
A) epicardium.
B) myocardium.
C) endocardium.
D) modified pericardium.
39) Semilunar valves are located
A) between the atria and the ventricles.
B) between the ventricles and the great arteries.
C) between the great veins and the atria.
D) only between the left ventricle and the aorta.
40) A condition in which the ventricles are unable to pump blood efficiently because of rapid, random contraction of cardiac muscle fibers is called
A) atrial fibrillation.
B) ventricular fibrillation.
C) pulmonary arterial hypertension.
D) congestive heart failure.