Which of the following statements about conducting system of the heart is INCORRECT? I. Mass of nodal tissue seen in the lower-left corner of the right atrium is the sinoatrial node. II. The nodal musculature can generate action potentials only in response to external stimuli. III. The number of action potentials that could be generated in a minute varies at different parts of the nodal system. IV. The SAN can generate the maximum number of action potentials, i.e., 80-85 min-1.

Question

Which of the following statements about conducting system of the heart is INCORRECT? I. Mass of nodal tissue seen in the lower-left corner of the right atrium is the sinoatrial node. II. The nodal musculature can generate action potentials only in response to external stimuli. III. The number of action potentials that could be generated in a minute varies at different parts of the nodal system. IV. The SAN can generate the maximum number of action potentials, i.e., 80-85 min-1. (A) I, II, III and IV (B) I, II and IV (C) II, III and IV (D) I, II and III

Tardigrade Admin · Accepted Answer

The specialized tissue(nodal tissue) present in the cardiac muscles, is located in the upper right corner of the right atrium. This tissue is autoexcitable, and generates impulses without any external stimuli, but with a variable number of action potential being generated in different parts of the nodal system. The SAN generates 70-75 action potential per min and is also known as the pacemaker of the heart.