Which property is associated with a muscle fiber having a fully developed sarcolemma and sarcoplasmic reticulum?

Which property is associated with a muscle fiber having a fully developed sarcolemma and sarcoplasmic reticulum?

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

Answer: (A)

The key idea is that skeletal muscle fibers are built to contract quickly and forcefully through a highly developed membrane system and calcium storage. The sarcolemma is the cell membrane that conducts electrical signals into the fiber, and the sarcoplasmic reticulum stores and releases calcium to trigger contraction. In skeletal muscle, the sarcoplasmic reticulum is especially extensive and works with transverse tubules to release Ca2+ rapidly along the fiber, supporting rapid, voluntary movements. Cardiac muscle also uses calcium for contraction but its internal calcium handling and cell connections differ, and smooth muscle has a less developed sarcoplasmic reticulum and lacks the same organized triad system. Nervous tissue isn’t muscular tissue at all. So this combination of a fully developed sarcolemma and sarcoplasmic reticulum best matches skeletal muscle tissue.

The key idea is that skeletal muscle fibers are built to contract quickly and forcefully through a highly developed membrane system and calcium storage. The sarcolemma is the cell membrane that conducts electrical signals into the fiber, and the sarcoplasmic reticulum stores and releases calcium to trigger contraction. In skeletal muscle, the sarcoplasmic reticulum is especially extensive and works with transverse tubules to release Ca2+ rapidly along the fiber, supporting rapid, voluntary movements. Cardiac muscle also uses calcium for contraction but its internal calcium handling and cell connections differ, and smooth muscle has a less developed sarcoplasmic reticulum and lacks the same organized triad system. Nervous tissue isn’t muscular tissue at all. So this combination of a fully developed sarcolemma and sarcoplasmic reticulum best matches skeletal muscle tissue.