Skeletal muscle- myofibrils The structural and functional subunit of the muscle fiber y They contribute to Muscle fibre Myofibrils the formation of 友 transverse-striation They have a bands H bands m lines i bands and z linesSkeletal muscle-myofibrils ◼ The structural and functional subunit of the muscle fiber. ◼ They contribute to the formation of transverse-striation. ◼ They have A bands, H bands, M lines, I bands and Z lines