The refractory period in adult cardiac muscle extends throughout nearly the whole period of the action potential, thereby limiting "circus" patterns of myocardial depolarization and inefficient pumping of blood. ( T / F )
Vascular resistance to blood flow is equal to perfusion pressure divided by (________).
Concerning the adult cardiac cycle: left ventricle volume is greatest during:
1. systolic ventricular ejection
2. rapid ventricular filling
3. isovolumic ventricular contraction
4. ventricular diastasis
A pressure of 25/4 (mmHg) and hemoglobin-oxygen saturation of 75% is representative of normal conditions for the adult in the:
1. right ventricle
2. left ventricle
3. pulmonary vein
4. pulmonary artery
5. aorta
What phase of the adult cardiac cycle are you in, when the ventricular volume is decreasing fast, aortic pressure is rising, and aortic flow is high?
1. isovolumic ventricular systole
2. early ventricular ejection
3. isovolumic ventricular relaxation
4. rapid ventricular filling
The second heart sound in the adult is caused by:
1. closure of the A-V valves (tricuspid & mitral)
2. ejection of blood from the ventricle
3. atrial contraction
4. ventricular contraction
5. closure of the aortic and pulmonic valves
The P₅₀ value is the partial pressure of oxygen which gives 50% saturation of hemoglobin. ( T / F ).