Q.

In forg’s heart, there are muscular ridges which consist of fibers called 
 


Ans.

(d) In frog’s heart, a number of muscular ridges called columnae carne projected from the wall of ventricle into its cavity, dividing the peripheral part of the cavity into a number of pockets. It prevent suction that would occur with a flat surfaced membrane and thus impairs the heart’s ability to pump efficiently.