Which order of stages is correct for one cardiac cycle?

• Ventricular systole, atrial systole, general diastole
• General diastole, ventricular systole, atrial systole
• Atrial systole, ventricular systole, general diastole

What does systole mean?

• Relaxation and filling of a chamber
• Contraction of atria or ventricles
• Closing of all four valves at once

What makes a heart valve open?

• A nerve signal firing into the cusps
• Pressure behind it exceeding pressure ahead of it
• The heart muscle tugging the valve open

On a trace, ventricular pressure is falling steeply after its peak. Which stage is this?

• Atrial systole topping up the ventricles
• Ventricular diastole with the chambers refilling
• Ventricular systole ejecting blood fast

Ventricular pressure has just risen above atrial pressure. What happens?

• The atrioventricular valves shut with the first heart sound
• The semilunar valves open and ejection starts
• Blood flows back freely into the atria

Ventricular pressure has just passed artery pressure on the way up. What happens?

• The atrioventricular valves reopen at once
• Semilunar valves open and ejection begins
• The semilunar valves close to block backflow

A ventricle holds 140 ml before systole and 70 ml after. What is the stroke volume in ml?

Answer: ______________

On a trace, ventricular pressure has just fallen below artery pressure. What happens and why?

• Semilunar valves shut as backflow starts
• Semilunar valves open, as ejection restarts
• Atrioventricular valves open, as atria contract