Question

Which of the following statement (s) is (are) true about heart?
(i) Left atrium receives oxygenated blood from different parts of the body while right atrium receives deoxygenated blood from lungs.
(ii) Left ventricle pumps oxygenated blood to different body parts while right ventricle pumps deoxygenated blood to lungs.
(iii) Left atrium transfers oxygenated blood to right ventricle which sends it to different parts of the body.
(iv) Right atrium receives deoxygenated blood from different parts of the body while left ventricle pumps oxygenated blood to different parts of the body.

• A. (i)
• B. (ii)
• C. (ii) and (iv)
• D. (i) and (iii)

Answer 1

The correct option is C (ii) and (iv)

Humans show double circulation. The blood pumped by the right ventricle enters the pulmonary artery, whereas the left ventricle pumps blood into the aorta. The deoxygenated blood pumped into the pulmonary artery is passed onto the lungs from where the oxygenated blood is carried by the pulmonary veins into the left atrium. This pathway constitutes the pulmonary circulation. The oxygenated blood entering the aorta is carried by a network of arteries, arterioles and capillaries to the tissues from where the deoxygenated blood is collected by a system of venules, veins and vena cava and emptied into the right atrium. This is the systemic circulation. The systemic circulation provides nutrients, O${}_2$ and other essential substances to the tissues and takes CO${}_2$ and other harmful substances away for elimination.