BIO 322 Practice Exam Questions and Correct Answers

What is true about atrial, aortic, and ventricular pressures? A. Aortic pressure is always greater then ventricular pressure which is always greater then atrial pressure. B. Atrial pressure is always greater then ventricular pressure which is always greater then aortic pressure. C. Ventricular pressure is greater than aortic pressure when the aortic semilunar valve is open. D. Aortic pressure is greater than ventricular pressure when the aortic semilunar valve is open. C. Ventricular pressure is greater than aortic pressure when the aortic semilunar valve is open. What is end systolic volume? A. It is usually around 50 ml and is decreased by increased contractility. B. It is usually around 50 ml and is increased by increased contractility. C. It increases to around usually around 130 ml when sympathetic activity is high. D. Is very low when a person is at rest, or lying down. A. It is usually around 50 ml and is decreased by increased contractility. Calculate the osmotic concentration of a solution containing 100 mM NaCl and 50 mM glucose. A. 250 mOsm/L B. 300 Osm/L C. 200 Osm/L D. 400 mOsm/L A. 250 mOsm/L The plateau phase of the cardiac muscle action potential is shown by the letter ___ and results from A. C, increased membrane permeability to potassium ions (K channels open) B. B, increased membrane permeability to calcium ions (Ca channels open). C. C, increased membrane permeability to chloride ions (Cl channels open). D. A, an increased membrane permeability to sodium ions (Na channels open). B. B, increased membrane permeability to calcium ions (Ca channels open)