Muscle drawing

Muscles and muscular system. Representation of a cutaway and zoom in on a contracted muscle and its structure, from left to right: - tendon - muscle - muscle fiber bundle - muscle fiber - myofibril with actin and myosin fibers. The contracted myofibril in section shows the interweaving of fine (actin in red) and thick (myosin in blue) filaments. The sarcolemma is limited between the two darker pink bands on the cut. (Photo by: JACOPIN/BSIP/Universal Images Group via Getty Images)