Which primitive area of the heart will give rise to the right ventricle? a. bulbus cordis b. primitive ventricle c. sinus venosus d. truncus arteriosus Which primitive area of the heart will give rise to the right ventricle? a. bulbus cordis b. primitive ventricle c. sinus venosus d. truncus arteriosus

The first heart sound represents which portion of the cardiac cycle? a. atrial systole b. ventricular systole c. closing of the atrioventricular valves d. closing of the semilunar valves

Which portion of the ECG corresponds to repolarization of the atria? a. P wave b. QRS complex c. T wave d. none of the above: atrial repolarization is masked by ventricular depolarization

The pulmonary trunk and aorta are derived from which primitive heart structure? a. bulbus cordis b. primitive ventricle c. sinus venosus d. truncus arteriosus

The myocardium would be the thickest in the ________. a. left atrium b. left ventricle c. right atrium d. right ventricle

The cardiac cycle consists of a distinct relaxation and contraction phase. Which term is typically used to refer ventricular contraction while no blood is being ejected? a. systole b. diastole c. quiescent d. isovolumic contraction

Which of the formed elements arise from myeloid stem cells?

a. B cells

b. natural killer cells

c. platelets

d. all of the above

Hemolytic disease of the newborn is a risk during a subsequent pregnancy in which ________. a. a type AB mother is carrying a type O fetus b. a type O mother is carrying a type AB fetus c. an $Rh^+$ mother is carrying an $Rh^−$ fetus d. an $Rh^−$ mother is carrying a second $Rh^+$ fetus

Which valve separates the left atrium from the left ventricle? a. mitral b. tricuspid c. pulmonary d. aortic

The process in which antibodies attach to antigens, causing the formation of masses of linked cells, is called ________. a. sensitization b. coagulation c. agglutination d. hemolysis

Which chamber initially receives blood from the systemic circuit? a. left atrium b. left ventricle c. right atrium d. right ventricle

Of the three germ layers that give rise to all adult tissues and organs, which gives rise to the heart? a. ectoderm b. endoderm c. mesoderm d. placenta

T and B lymphocytes ________. a. are polymorphonuclear b. are involved with specific immune function c. proliferate excessively in leukopenia d. are most active against parasitic worms

A molecule of hemoglobin ________. a. is shaped like a biconcave disk packed almost entirely with iron b. contains four glycoprotein units studded with oxygen c. consists of four globin proteins, each bound to a molecule of heme d. can carry up to 120 molecules of oxygen