question_answer 6)

What is meant by double circulation? What is its significance? 

Answer:

Double circulation In double circulation, the blood passes twice through the heart during one complete cycle. Double circulation is carried out by two ways. (i) Pulmonary circulation (ii) Systemic circulation Significance Double Circulation In birds and mammals, oxygenated and deoxygenated blood received by the left and right atria respectively passes on to the ventricles of the same sides. The ventricles pump it out without mixing up, i.e., two separate circulatory pathways are present in these organisms. This is the importance of double circulation.