In human beings, the coordination of the contraction of the heart chambers is brought about by a pacemaker located in the walls of the

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Q: 44 (IES/2002)
In human beings, the coordination of the contraction of the heart chambers is brought about by a “pacemaker” located in the walls of the

question_subject: 

Science

question_exam: 

IES

stats: 

0,11,17,9,11,6,2

keywords: 

{'heart chambers': [0, 0, 1, 0], 'left ventricle': [0, 0, 8, 0], 'right ventricle': [0, 0, 2, 1], 'pacemaker': [1, 0, 0, 0], 'right auricle': [0, 0, 2, 1], 'walls': [2, 1, 1, 4], 'coordination': [0, 1, 1, 0], 'auricle': [0, 0, 1, 0]}

The correct answer is option 2: right auricle. The coordination of the contraction of the heart chambers in human beings is regulated by a "pacemaker" known as the sinoatrial (SA) node. The SA node is located in the walls of the right auricle, which is one of the two upper chambers of the heart, also known as atria.

The SA node generates electrical signals that initiate the contraction of the heart chambers. These signals are then transmitted through specialized conducting tissues, such as the atrioventricular (AV) node, to coordinate the contraction and relaxation of the heart chambers in a synchronized manner.

Option 1: Left auricle is incorrect because the SA node is not located in the left auricle.

Option 3: Left ventricle is incorrect because the ventricles are the lower chambers of the heart and are responsible for pumping blood out of the heart. The SA node is not located in the left ventricle.

Option 4: Right ventricle is incorrect for the same reason mentioned above.

Therefore, the correct answer is option 2: right auricle.