Question

In frog's heart,there are conducting cardiac muscles which consist of fibres called

• A. Myonemes
• B. Purkinje fibres
• C. Telodendria
• D. Columnae carneae

Answer 1

The correct option is B Purkinje fibres

The heart wall of frog is composed of epicardium, myocardium and endocardium. The myocardium is composed of branched and striated yet involuntary cardiac muscles which contracts and relaxes rhythmically at a fixed rate. The fibres of the self-excitatory and conducting muscle of the heart are of three types-nodal fibres, transitional fibres and Purkinje fibres. In frog heart, a number of muscular ridges called 'columnae carnae' project from the wall of ventricle into its cavity, dividing the peripheral part of the cavity into a number of pockets.

So, the correct answer is 'Purkinje fibres'.