Question: the thin myofilaments of skeletal muscle are composed chiefly of?
Answer: The larger, or thick myofilaments are made of the protein, myosin, and the smaller thin myofilaments are chiefly made of the protein, actin. Let's discuss each myofilament in turn. Each actin molecule is composed of two strands of fibrous actin (F actin) and a series of troponin and tropomyosin molecules.