Which artery carries deoxygenated blood instead of oxygenated blood?

Which valve is located between the left atrium and the left ventricle?

During each cardiac cycle, prominent sounds are produced which can be easily heard through a stethoscope. They are

The rate of heart beat per minute is highest in case of

Which structure acts as the pacemaker of the heart?

The valves in the heart allow the blood flow in which direction?
$I.$ From atria to ventricles
$II.$ From ventricles to pulmonary artery
$III.$ From pulmonary artery to aorta
Choose the correct option.