Question
Biology Question on Circulatory Pathways
The pace maker of heart is
A
AV node
B
SA node
C
bundle of His
D
purkinje fibres
Answer
SA node
Explanation
Solution
Pacemaker is a group of modified cardiac muscle cells in sinus venosus of vertebrate heart. In mammals and birds, S.A. node (sino auricular node) lies in right atrial walls near superior vena cava. The electrical current generated spreads to adjacent purkinje fibres and from these to atrial muscle cells which contract together.