Statement A : Intercalated discs are important regions of cardiac muscle cells.Statement B : Intercalated discs function as boosters for muscle contraction waves.

Cardiac muscle cells are short cylindrical cells joined end to end and by side branching to form a network. Intercalat discs  contain  gap junctions which allow the cells to contract as a unit.. Intercalated discs are the specialised regions of the cell membranes. As cardiac muscle possesses considerable rhythmicity and generates its own wave of excitation, these discs function as boosters for muscle contraction wave.