Question

Which part of the human heart carries only pure blood?
A. Left ventricle
B. Left auricle
C. Both A and B
D. Right ventricle and right auricle

Answer 1

Hint: Blood vascular system and the lymphatic system are the two constituents of the human circulatory system. Both the systems are of closed type. Heart, blood, and blood vessels form the blood vascular system.

Complete answer:
The human heart is four-chambered. It has two upper chambers called the atria which are relatively small and two larger lower chambers which are called the ventricles. The right and the left atria are separated by the interatrial septum which is a thin muscular wall. On the other hand, an interventricular septum separates the left and right ventricles. This septum is thick-walled. The atrioventricular septum separates the atrium and ventricle of the same side. Each atrium has an appendage called the auricle which increases the surface area of the atrium. Systemic and pulmonary circulation constitute double circulation. In the systemic circulation, oxygenated or pure oxygen flows from the left ventricle to all parts of the body and deoxygenated blood flows from various parts to the right atrium. In pulmonary circulation, deoxygenated blood flows from the right ventricle to the lungs and then oxygenated blood is returned to the left atrium from the lungs. It is therefore understandable that the left part of the human heart carries pure or oxygenated blood.
Thus, the correct option is C, i.e., Both A and B.

Note: The oxygen-rich blood from the lungs is received by the left atrium via the pulmonary veins. Thus, the modulation of the left ventricular filling and cardiovascular performance is the principal role of the left atrium.