The right part of the heart is concerned with venous blood and left part with the oxygenated blood. In one complete circuit in the body the blood passes twice through the heart, once through its right side and then through its left side.
This type of bi-circulation of blood is known as double circulation. The complete separation of ventricles into two chambers enables the venous and oxygenated blood not to mix. However, the circulation of blood in the body parts from the heart can be represented as given below.
Oxygenated blood – left auricle – left ventricle – carotico systemic aorta – arteries – arterioles – and arterial capillaries – organs – venous capillaries and venules (venous blood) – veins – precavals and postcaval – right auricle – right ventricle – pulmonary aorta – pulmonary aorta – pulmontary arteries – lungs (for purification) – pulmonary veins – left auricle (oxygenated blood).