NEETZoologyBody Fluids and Circulation
Answer the correct option w.r.t diagram shown. Assertion: SA node is called the pacemaker. Reason: The SAN can generate the maximum number of action potentials, i.e., 70-75 min–1.
Options
- ABoth assertion and reason are correct and reason is the correct explanation of the assertion.
- BBoth assertion and reason are correct but reason is not the correct explanation of assertion.
- CThe assertion is correct but the reason is wrong.
- DBoth assertion and reason are incorrect
Correct answer
A. Both assertion and reason are correct and reason is the correct explanation of the assertion.
Step-by-step solution
The SAN can generate the maximum number of action potentials, i.e., 70-75 min–1, and is responsible for initiating and maintaining the rhythmic contractile activity of the heart. Therefore, it is called the pacemaker. Our heart normally beats 70-75 times in a minute (average 72 beats min–1).