This low power micrograph shows a longitudinal section of this magnification, is connective tissue, the perimysium (P). Also evidentstriated muscle. The muscle tissue within the muscle is arin the micrograph is a nerve (Nv).
ranged in a series of fascicles (F). The individual muscle fibers within a fascicle are in close proximity to one another,
Skeletal muscle, human, H&E, ×33.
This micrograph reveals part of a muscle that has been cut in cross section. Again, individual bundles of muscle fibers or fascicles (F) can be readily identified. In contrast to the previous micrograph, even at this low magnification, upon careful  examination, individual muscle fibers (MF) can be identified in many of the fascicles. Each is bounded by connective tissue, which constitutes the perimysium (P). Also identifiable in this micrograph is a dense connective tissue surrounding the muscle, namely epimysium (E).
Skeletal muscle, human, H&E, ×256; inset ×700.
This higher magnification of a longitudinal section of a muscle reveals two muscle fibers (MF). At this magnification, the cross-banding pattern is just perceptible. With few exceptions, the nuclei (N), which tend to run in linear arrays, belong to the muscle fibers. Also evident in this micrograph is a small blood vessel (BV). The inset, taken from a gluteraldehyde fixed plastic embedded specimen, is a much higher magnification of a portion of two muscle fibers. The major bands are readily identifiable at this magnification and degree of specimen preservation. The thick, dark stained band is the A-band. Between A-bands is a lightly stained area, the I-band, which is bisected by the Z-line. The two elongate nuclei (N) belong to the muscle fibers. Below them are a capillary (C) and a portion of an endothelial cell nucleus (End). At this higher magnification, the endothelial nuclei, as well as the nuclei of the fibroblasts, can be distinguished from the muscle cell nuclei by their smaller size and heterochromatin giving them a dark stain. The muscle cell nuclei (N) exhibit more euchromatin with a speckling of heterochromatin, thus given them a lighter staining appearance.
Skeletal muscle, human, H&E, ×256.
In this cross section, individual muscle fibers (MF) are readily discernable in contrast to identifying individual muscle fibers in longitudinal sections. For example, if one imagines a cut crossing a number of cells (see dashed line), the close proximity of the muscle cells can mask the boundary between individual cells within a fascicle when observed in the opposite or longitudinal plane. The connective tissue (CT) that is readily apparent here belongs to the perimysium, which separates fascicles. The nuclei of the individual fibers are located at the periphery of the cell. At this magnification, it is difficult to distinguish between occasional fibroblasts that belong to the endomysium from the nuclei of the muscle cells.
KEY BV, blood vessel C, capillary CT, connective tissue E, epimysium End, endothelial cell nucleus F, fascicles MF, muscle fibers N, nuclei Nv, nerve P, perimysium