False-colour transmission electron micrograph (TEM) of human striated muscle. Striated muscle cells are elongated, hence their description as fibres. Each cell has several nuclei positioned just below the sarcolemma, the name given to the cell membrane of muscle cells. Running the length of each fibre are contractile proteins arranged in thin threads called myofibrils. More prominent is the banding across the fibres, caused by myofibrils being composed of alternating light & dark sections. Magnification: x780 at 35mm size.