SKELETAL MUSCLE – 1
Striated skeletal muscle fibers constitute what is commonly called skeletal muscle.
The fibers are long, cylindrical cells that can reach several centimeters in length. The cells are multinucleated, and their nuclei are positioned peripherally, close to the plasma membrane. The nuclei have clear chromatin and are elliptical, resembling a cigar shape. The best way to recognize the peripheral position of the nuclei is in cross-sections of the fibers – see the second diagram.
In longitudinal sections of the fibers, another important characteristic of this type of muscle fiber can be observed – the transverse striations (bands) in the cytoplasm.
The fibers are long, cylindrical cells that can reach several centimeters in length. The cells are multinucleated, and their nuclei are positioned peripherally, close to the plasma membrane. The nuclei have clear chromatin and are elliptical, resembling a cigar shape. The best way to recognize the peripheral position of the nuclei is in cross-sections of the fibers – see the second diagram.
In longitudinal sections of the fibers, another important characteristic of this type of muscle fiber can be observed – the transverse striations (bands) in the cytoplasm.
The lower image is a low magnification of a skeletal muscle section in which most of the fibers were sectioned transversely.
A smaller number of fibers were sectioned longitudinally – they are highlighted in light blue. These fibers show their length. Due to the low C of the image, it is not possible to observe its transverse striation.
Fibers in longitudinal section
Fibers in cross section
Striated skeletal muscle. Staining: hematoxylin and eosin. Magnification: small.
