Ventricular filling occurs as a purely passive process and is completely dependent upon atrial contraction.
The major reason the mitral valve closes at the beginning of ventricular contraction is because of increasing pressure in the ventricle.
The aortic valve closes at the end of systolic ejection because ventricular pressure falls below aortic pressure.
The right and left heart pump exactly the same amount of blood per beat in every cardiac cycle.
The right and left ventricles begin and end contractions at exactly the same time.
The sounds heard through the stethoscope when taking blood pressure by the auscultatory method are made by heart valves opening and closing.