12.Which of the following is correct regarding the events of the cardiac cvcle? A.Closures of the va heart sound B.Ventricular pressure is increasing during isovolumic xation phas C.Ventricular volume is the greatest at the end of systol D.The semilunar valves are open at the end of diastole E.The left ventricle ejects blood into the pulmonary circulation A 13.Which of the following would NOT be an effect of ACh on the heart? A.Resting potential (maximal diastole potential)more negative B.K'channel permeability decreases C.Myocardial contractility decreases E.The depolarization velocity at B 14.When a person stands up suddenly after lying horizontally for a long period of time,his venous blood will be redistributed more evenly between leg veins and th acie veins.This will immediately result in A.a decrease in central venous pressure(CVP) B.a decrease in cardiac output(CO) C.an increase in central venous pressure (CVP) D.an increase in cardiac output(CO) E.Aand B E 15.Which of the following is the effect factors of Cardiac output? A.Afterload B Preload C.Heart rate D.Contractility E.All of the above E 16.The venous side of the circulation is characterized by A.low pressure B.low resistance to flow C.large volume capacity D.rich sympathetic and parasympathetic innervation E.all of the above except D. E 17.The arterial side of the circulation is characterized by A.turbulent blood flow12. Which of the following is correct regarding the events of the cardiac cycle? A. Closures of the atrioventricular valves produce the first heart sound B. Ventricular pressure is increasing during isovolumic relaxation phase C. Ventricular volume is the greatest at the end of systole D. The semilunar valves are open at the end of diastole E. The left ventricle ejects blood into the pulmonary circulation A 13. Which of the following would NOT be an effect of ACh on the heart? A. Resting potential (maximal diastole potential) more negative B. K+ channel permeability decreases C. Myocardial contractility decreases D. Ca2+ channel permeability decreases E. The depolarization velocity at phase 4 decreases B 14. When a person stands up suddenly after lying horizontally for a long period of time, his venous blood will be redistributed more evenly between leg veins and thoracic veins. This will immediately result in A. a decrease in central venous pressure (CVP) B. a decrease in cardiac output (CO) C. an increase in central venous pressure (CVP) D. an increase in cardiac output (CO) E. A and B E 15. Which of the following is the effect factors of Cardiac output ? A. Afterload B. Preload C. Heart rate D. Contractility E. All of the above E 16. The venous side of the circulation is characterized by A. low pressure B. low resistance to flow C. large volume capacity. D. rich sympathetic and parasympathetic innervation E. all of the above except D. E 17. The arterial side of the circulation is characterized by A. turbulent blood flow