Sarcomeres are the smallest functional contractile unit of muscle. and myofibrils are striated muscle organelles that are comprised of sarcomeres that are strictly aligned in series. Furthermore. passive forces in sarcomeres and myofibrils are almost exclusively produced by the structural protein titin. https://www.spidertattooz.com/Essie-Gel-Couture-Transition-Piece-1754-p14911/