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Muscle tissue - Cardiac muscle tissue, found in the heart, produces coordinated and automatic contractions

4 important questions on Muscle tissue - Cardiac muscle tissue, found in the heart, produces coordinated and automatic contractions

What is an intercalated disk?

At an intercalated disk, the sarcolemmas of two adjacent cardiac muscle cells are extensively intertwined and bound together by gap junctions and desmosomes. These connections help stabilize the position of adjacent cells and maintain the three-dimensional structure of the tissue. Also ions are allowed to move from one cll to another which leads to the rhythmically beating of the heart.

What is a functional syncytium?

A functional syncytium is a fused mass of cells.

Compare and contrast skeletal muscle tissue and cardiac muscle tissue.

Compared to skeletal muscle tussue cardiac muscle tissue (1) has relatively small cells; (2) has cells with a centrally located nucleus (some may contain two or more nuclei); (3) has T tubules that are short and broad and do not form triads; (4) has and SR that lacks terminal cisternae and has tubules that contact the plasma membrane as well as the T tubules; (5) has cells that are nearly totally dependent on aerobic metabolism as an energy source; and (6) contains intercalated discs that assist in stabilizing tissue structure and spreading action potentials.

What feature of cardiac muscle tissue allows the heart to act as a functional syncytium?

Cardiac muscle cells are joined by gap junctions, which allow ions and small molecules to flow directly between cells. As a result, action potential generated in one cell spread rapidly to adjacent cells. Thus, all the cells contract simultaneously, as if they were a single unit (a syncytium)