Interactive Physiology Worksheet:
Cardiovascular System: Cardiac Cycle
differences of blood pressure
1. Valves open in response to ______________________________________ on their two sides.
2. List the chambers/vessels that the four valves connect:
Chamber
Right ventricle
Left ventricle
Valve
Pulmonary semilunar
Aortic semilunar
Chamber/Vessel
Pulmonary trunk
Aorta
Left atrium
Mitral
Left ventricle
Right atrium
Tricuspid
Right ventricle
mid to late
diastole
3. a. Ventricular filling occurs during ________________________ ventricular
________________. av valves
atrioventricular
b. Blood flows through the ____________________, or __________, valves into the ventricles.
4. During ventricular systole, what closes the AV valves?
interventricular pressure is greater then atrial pressure
_____________________________________________________________________________
5. During ventricular systole, what opens the semilunar valves? interventricular pressure is greater than pressure in pulmonary trunk and aorta _____________________________________________________________________________
6.
During isovolumetric relaxation, what closes the semilunar valves? _____________________________________________________________________________ blood flow back toward the heart due to aortic pressure being greater than interventriuclar pressure
7. During isovolumetric relaxation, what opens the AV valves? atrial pressure is greater than interventricular pressure
_____________________________________________________________________________
8. Why is hypertension hard on the heart?
ventricular pressure must rise higher to open the semilunar valves; the same increase in a normal BP, less _______________________________________________________________________________
blood is ejected in a hypertensive case so the heart with hypertension must work harder to eject the same ______________________________________________________________________ SV
__________________________________________________________________________
9. Looking at the Ventricular Volume graph, the stroke volume is approximately how many ml? 70
________________
10.
During the four phases listed below, state whether the AV and semilunar valves are open or
closed:
Phase
AV Valves
Semilunar Valves
Ventricular filling
Open
Closed
Isovolumetric contraction
Closed
Closed
Ventricular ejection
Closed
Open
Isovolumetric relaxation
Closed
Closed