MAIN HISTOLOGICAL FEATURES OF THE MUSCLE FIBERS
Skeletal muscle fibers
Skeletal muscle fibers are long, cylindrical cells that may extend nearly the entire length of the muscle to which they belong. They are multinucleated, and their numerous nuclei are located at the periphery of the fiber, immediately beneath the plasma membrane. Skeletal muscle fibers are striated because, when viewed under a microscope, their cytoplasm shows a regular pattern of characteristic transverse bands (striations).
Skeletal muscle fibers are long, cylindrical cells that may extend nearly the entire length of the muscle to which they belong. They are multinucleated, and their numerous nuclei are located at the periphery of the fiber, immediately beneath the plasma membrane. Skeletal muscle fibers are striated because, when viewed under a microscope, their cytoplasm shows a regular pattern of characteristic transverse bands (striations).
Smooth muscle fibers
Smooth muscle cells are called “smooth” because their cytoplasm does not show the transverse striations characteristic of skeletal and cardiac muscle when viewed in longitudinal sections under a microscope. They are spindle-shaped, with tapered ends, and their nucleus is centrally located within the cell.
The position of the nuclei in longitudinal and transverse sections of muscle cells is an important histological feature that helps distinguish their different types.
