Skeletal muscle

Several myofibrils and the myofilaments that comprise them demonstrate the highly ordered arrangement of the thin myofilaments surrounding the thick myofilaments. Though not well preserved in this tissue, the sarcoplasmic reticulum (comparable to endoplasmic reticulum) is present around the periphery of the myofibril. 40,000x

Thin filaments are primarily composed of actin protein. They surround the thick filaments which are primarily composed of myosin protein. Each thick filament is surrounded by six thin filaments. The sliding of these filaments produces muscle contraction.

Thin filaments are primarily composed of actin protein. They surround the thick filaments which are primarily composed of myosin protein. Each thick filament is surrounded by six thin filaments. The sliding of these filaments produces muscle contraction.

Several myofibrils and the myofilaments that comprise them demonstrate the highly ordered arrangement of thin myofilaments surrounding the thick myofilaments. Though not well preserved in this tissue, the sarcoplasmic reticulum (comparable to endoplasmic reticulum) is present around the periphery of the myofibril. 40,000x

Several myofibrils and the myofilaments that comprise them demonstrate the highly ordered arrangement of thin myofilaments surrounding the thick myofilaments. Though not well preserved in this tissue, the sarcoplasmic reticulum (comparable to endoplasmic reticulum) is present around the periphery of the myofibril. 40,000x