Which muscle tissue forms the walls of the heart and contains intercalated discs?

Which muscle tissue forms the walls of the heart and contains intercalated discs?

• A. Skeletal muscle tissue
• B. Cardiac muscle tissue
• C. Smooth muscle tissue
• D. Nervous tissue

Answer: (B)

Cardiac muscle tissue forms the walls of the heart. It has distinctive intercalated discs that join neighboring cardiac muscle cells, providing both strong mechanical connections through desmosomes and rapid electrical coupling via gap junctions. This setup lets ions flow quickly between cells, so the heart can beat as a coordinated unit. Cardiac muscle fibers are branched and usually have a single central nucleus, and they are striated like skeletal muscle but operate involuntarily under autonomic control. In contrast, skeletal muscle is attached to bones and is voluntary, and smooth muscle lines hollow organs and lacks intercalated discs. Nervous tissue isn’t muscular at all.

Cardiac muscle tissue forms the walls of the heart. It has distinctive intercalated discs that join neighboring cardiac muscle cells, providing both strong mechanical connections through desmosomes and rapid electrical coupling via gap junctions. This setup lets ions flow quickly between cells, so the heart can beat as a coordinated unit. Cardiac muscle fibers are branched and usually have a single central nucleus, and they are striated like skeletal muscle but operate involuntarily under autonomic control. In contrast, skeletal muscle is attached to bones and is voluntary, and smooth muscle lines hollow organs and lacks intercalated discs. Nervous tissue isn’t muscular at all.