Skeletal muscle tissue and cardiac muscle tissue have some different structures and functions. what cardiac muscle structures unify the heart's electric current, allowing the entire organ to contract smoothly?

The sarcolemmas from adjacent cells bind together at the intercalated discs. The answer is Intercalated discs, this join cardiocytes end to end. Complex structure with three features NOT found in skeletal muscle. Which helps support the synchronized contraction of the muscle.

Intercalated discs

Explanation:

Intercalated discs are thickening of the plasma membrane of cardiac muscle cells and are formed when these cells are attached end to end. Intercalated discs have desmosomes and gap junctions. Desmosomes serves to hold the cardiac muscle fiber together during contraction of cardiac muscles and impart strength. Function of gap junctions is to serve as path for immediate conduction of electric signal to ensure synchronized contraction of cardiac muscle cells.

organ system-an organ system is a group of organs that work together to perform one or more functions. each does a particular job in the body, and is made up of certain tissues.