CCI Practice Exam questions with correct answers

At what time during fetal growth is the heart first fully developed? Answer 40 Days Which of the following L-R shunts is the last to close in the normal post partum period? When does it close? Answer Patent Foramen Ovale closing at the end of the first week During the resting state, which of the following ions are pumped out of the cells of the myocardium? Answer Sodium Following electrical depolarization of the myocardial cell membrane, which ion rushes in first, and which ion rushes in later? Answer sodium followed by calcium Which ion helps slow heart muscle contraction? Answer potassium In the cardiac cell action potential, what phases are included in the absolute refractory period? Answer Phases 1 into Phase 3 When contracting against which of the following pressures will the velocity of muscle cell contraction be most rapid? Answer lowest pressure, the higher the pressure the more that it has to overcome in order to contract