SKELETAL MUSCLE – 1
Striated skeletal muscle fibers constitute the skeletal muscles.
The fibers are long cylindrical cells that can reach several centimeters in length. They are multinucleated, and their nuclei are positioned peripherally, close to the plasma membrane. The nuclei have clear chromatin and are elliptical like the shapeof a cigar. The best way to visualize the peripheral position of the nuclei is in cross-sections of the fibers – see the second diagram and the image.
A very important feature of these muscle fibers: transverse striations (or bands) in their cytoplasm, observed in lenghtwise sectioned fibers.
The fibers are long cylindrical cells that can reach several centimeters in length. They are multinucleated, and their nuclei are positioned peripherally, close to the plasma membrane. The nuclei have clear chromatin and are elliptical like the shapeof a cigar. The best way to visualize the peripheral position of the nuclei is in cross-sections of the fibers – see the second diagram and the image.
A very important feature of these muscle fibers: transverse striations (or bands) in their cytoplasm, observed in lenghtwise sectioned fibers.
The lower image is a low magnification of a skeletal muscle section in which most fibers were cross-sectioned. A few fibers (highlighted in light blue) are sectioned longitudinally. Because of the low magnification of the image, the transverse striation of their cytoplasm can not be seen.
Fibers in longitudinal section
Fibers in cross section
Striated skeletal muscle. Staining: hematoxylin and eosin. Low magnification.
