Select the MOST CORRECT answer. In a cardiac myocyte, changes inthe permeability of ions can lead to a change in membranepotential. In...
| | A conducting cardiac myocyte, the rapid depolarization is causedby the opening of T-type calcium channels. |
| | A contractile cardiac myocyte, the rapid depolarization iscaused by the opening of L-type calcium channels. |
| | Both conducting and contracting cardiac myocytes, the influx ofsodium and calcium cause the membrane to depolarize and the effluxof potassium causes repolarization. |
| | Both a) and b) are correct and c) is incorrect. |
| | a), b) and c) are all correct. |
Select the MOST CORRECT answer. An athlete was attempting toimprove their performance through doping, the act of taking illegaldrugs to increase red blood cell count. Unfortunately, the athleteexperienced a reduction of performance instead. Which of thefollowing best explains this outcome?
| | Heart rate and stroke volume were increased and thereforecardiac output was reduced. |
| | An increase in the viscosity of the blood caused totalperipheral resistance to increase, which reduced blood flow. |
| | A decrease in mean arterial pressure resulted because of theincrease in total blood volume. Because the bulk blood flow wasequal between both sides of the heart, the stroke volume decreasedover time. |
| | Both a) and b) are correct and c) is incorrect. |
| | a), b) and c) are all correct. |
