Review Questions
REVIEW QUESTIONS
1. Which of the following is not important in preventing backflow of blood?
a chordae tendineae
b papillary muscles
c AV valves
d endocardium
2. Which valve separates the left atrium from the left ventricle?
a mitral
b tricuspid
c pulmonary
d aortic
3. Which of the following lists the valves in the order through which the blood flows from the vena cava through the heart?
a tricuspid, pulmonary semilunar, bicuspid, aortic semilunar
b mitral, pulmonary semilunar, bicuspid, aortic semilunar
c aortic semilunar, pulmonary semilunar, tricuspid, bicuspid
d bicuspid, aortic semilunar, tricuspid, pulmonary semilunar
4. Which chamber initially receives blood from the systemic circuit?
a left atrium
b left ventricle
c right atrium
d right ventricle
5. The ________ layer secretes chemicals that help to regulate ionic environments and strength of contraction and serve as powerful vasoconstrictors.
a pericardial sac
b endocardium
c myocardium
d epicardium
6. The myocardium would be the thickest in the ________.
a left atrium
b left ventricle
c right atrium
d right ventricle
7. In which septum is it normal to find openings in the adult?
a interatrial septum
b interventricular septum
c atrioventricular septum
d all of the above
8. Which of the following is unique to cardiac muscle cells?
a Only cardiac muscle contains a sarcoplasmic reticulum.
b Only cardiac muscle has gap junctions.
c Only cardiac muscle is capable of autorhythmicity
d Only cardiac muscle has a high concentration of mitochondria.
9. The influx of which ion accounts for the plateau phase?
a sodium
b potassium
c chloride
d calcium
10. 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
11. Which component of the heart conduction system would have the slowest rate of firing?
a atrioventricular node
b atrioventricular bundle
c bundle branches
d Purkinje fibers
12. 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
13. Most blood enters the ventricle during ________.
a atrial systole
b atrial diastole
c ventricular systole
d isovolumic contraction
14. 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
15. Ventricular relaxation immediately follows ________.
a atrial depolarization
b ventricular repolarization
c ventricular depolarization
d atrial repolarization
16. The force the heart must overcome to pump blood is known as ________.
a preload
b afterload
c cardiac output
d stroke volume
17. The cardiovascular centers are located in which area of the brain?
a medulla oblongata
b pons
c mesencephalon (midbrain)
d cerebrum
18. In a healthy young adult, what happens to cardiac output when heart rate increases above 160 bpm?
a It increases.
b It decreases.
c It remains constant.
d There is no way to predict.
19. What happens to preload when there is venous constriction in the veins?
a It increases.
b It decreases.
c It remains constant.
d There is no way to predict.
20. Which of the following is a positive inotrope?
a Na+
b K+
c Ca2+
d both Na+ and K+