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Histology
(Canadian Campbell 2nd ed page 926) muscle.jpg)
Examine the prepared slide of striated muscle:
Striated muscle is influenced directly by the central nervous system and is under the control of the will. In most cases it is attached to the skeleton. An individual fiber may be from 1 to 40 mm long and 10 to 100mm in diameter (visible to the naked eye). This large cell is multinucleate i.e. it is a syncytium. The fibers are unbranched. Each fiber is enclosed in a thin membrane, the sarcolemma, which is a specialized cell membrane. The protoplasm of the fiber, sarcoplasm, contains five longitudinal myofibrils which extend throughout. Electron micrographs show that each myofibril is composed of two types of short myofilaments which are precisely arranged giving the appearance of transverse banding, the striations.
The section of striated muscle provided represents a longitudinal section of tongue. In tongue, the muscle cells are oriented in all planes so you should have no trouble finding cells cut in cross section and in longitudinal section. In cross sections of striated muscle, note the peripherally located nucleus. In longitudinal section, the cells show the syncytial structure as well as the prominent striations.
