Solution :
The heart receives impure blood (deoxygenated blood) from different parts of the body, and it pumps this blood to the lungs. The oxygenated blood or , pure blood from the lungs returns to the heart, which is pumped again into different parts of the body by the heart. Thus, the blood passes twice through the heart making one complete round through the body. This is called double circulation.
The two circuits involved in double circulation are:
i) Pulmonary circulation: This circuit deals with the lungs. The right ventricle of the heart pumps blood to the lungs. Blood that has been oxygenated by the lungs is collected by pulmonary veins and returned to the heart (left auricle).
ii) Systemic circulation: The body’s main blood flow is referred to as the systemic circulation. The left ventricle releases blood into the aorta, which then distributes it to various body organs. Deoxygenated blood is gathered from various bodily parts by veins and returned through the right auricle.
Significance of double circulation:
By separating oxygenated and deoxygenated blood, the body’s cells can receive oxygen more effectively. The circulatory system transports blood to the body’s tissues, whereas pulmonary circulation carries it to the lungs.