When are the AV valves open?
Understand the Problem
The question is asking about the timing of the opening of the atrioventricular (AV) valves in the context of heart physiology. This involves understanding the cardiac cycle and the phases in which these valves function.
Answer
When ventricular pressure is lower than atrial pressure.
The AV valves are open when ventricular pressure is lower than atrial pressure, resulting in ventricular relaxation.
Answer for screen readers
The AV valves are open when ventricular pressure is lower than atrial pressure, resulting in ventricular relaxation.
More Information
The atrioventricular (AV) valves open to allow blood flow from the atria to the ventricles when the ventricles are relaxed, facilitating efficient cardiac cycle functioning.
Tips
A common mistake is to assume AV valves are open during ventricular systole; they actually close to prevent backflow into the atria.
Sources
- CARDIAC CYCLE - cvil.ucsd.edu
- Biology Cardiac Cycle Info Sheet - montsaye.northants.sch.uk
