Which structure is the plasma membrane of a skeletal muscle fiber?

Which structure is the plasma membrane of a skeletal muscle fiber?

• A. Sarcolemma
• B. Endomysium
• C. Nucleus
• D. Intercalated Disc

Answer: (A)

The plasma membrane of a skeletal muscle fiber is the sarcolemma. This term refers to the specialized cell membrane that encloses each muscle fiber, separating its cytoplasm from the surrounding environment and enabling the electrical signals to trigger contraction. The endomysium is the delicate connective tissue layer that surrounds individual fibers, not the membrane itself. The nucleus is the cell’s genetic center located inside the fiber, beneath the sarcolemma, and intercalated discs are junctions found between cardiac muscle cells that help coordinate heart contractions, not present in skeletal muscle. So the sarcolemma is the correct structure.

The plasma membrane of a skeletal muscle fiber is the sarcolemma. This term refers to the specialized cell membrane that encloses each muscle fiber, separating its cytoplasm from the surrounding environment and enabling the electrical signals to trigger contraction. The endomysium is the delicate connective tissue layer that surrounds individual fibers, not the membrane itself. The nucleus is the cell’s genetic center located inside the fiber, beneath the sarcolemma, and intercalated discs are junctions found between cardiac muscle cells that help coordinate heart contractions, not present in skeletal muscle. So the sarcolemma is the correct structure.