These diagrams display the heart valves in cross-section from above during different points of the cardiac cycle. Which stages of the cardiac cycle are being shown?
- Adiagram 1: diastole; diagram 2: ventricular systole
- Bdiagram 1: atrial systole; diagram 2: diastole
- Cdiagram 1: ventricular systole; diagram 2: diastole
- Ddiagram 1: diastole; diagram 2: atrial systole