Question

The cardiac impulse is initiated and conducted further upto ventricle. The correct sequence of conduction of impulse is:

• A. $\begin{array}{cccc}\text{SA Node}& \text{AV Node}& \text{Purkinje fibre}& \text{AV Bundle}\end{array}$
• B. $\begin{array}{cccc}\text{SA Node}& \text{Purkinje fibre}& \text{AV Node}& \text{AV Bundle}\end{array}$
• C. $\begin{array}{cccc}\text{SA Node}& \text{AV Node}& \text{AV Bundle}& \text{Purkinje fibre}\end{array}$
• D. $\begin{array}{cccc}\text{SA Node}& \text{Purkinje fibre}& \text{AV Bundle}& \text{AV Node}\end{array}$

Answer 1

The correct option is C $\begin{array}{cccc}\text{SA Node}& \text{AV Node}& \text{AV Bundle}& \text{Purkinje fibre}\end{array}$

SA node is situated in the walls of the right auricle near the opening of the superior vena cava. In myogenic heart, the contraction is initiated by SA node.
The wave of contraction reaches AV node from SA node. From AV node, the contraction wave reaches the AV bundle and through purkinje fibres it spreads to the wall of ventricles.