The correct order of skeletal muscle structures from largest to smallest is: 1. fascicles, 2. muscle cell (or muscle fiber), 3. myofibril, 4. sarcomere, and 5. myofilament. Fascicles are bundles of muscle fibers, which are the individual muscle cells. Myofibrils are found within muscle cells, composed of repeating units called sarcomeres, which contain the myofilaments responsible for muscle contraction.