1.1 The structure of skeletal muscle fiber under lm Longitudinal section----- Shape of muscle fiber: Long cylindrical no branched Cross striations Nuclus: Multinucleated, oval, just beneath the sarcolemma(at its periphery) Sarcoplasm: filled with longitudinal parallel-arranged myofibrils(肌原纤维)1.1 The structure of skeletal muscle fiber under LM Shape of muscle fiber: Long cylindrical, No branched, Cross striations. Longitudinal section------- Nuclus: Multinucleated, oval, just beneath the sarcolemma (at its periphery). Sarcoplasm: filled with longitudinal parallel-arranged myofibrils（肌原纤维）