ANATOMY

Detailed explanation-1: -Myofibrils are composed of long proteins including actin, myosin, and titin, and other proteins that hold them together. These proteins are organized into thick, thin, and elastic myofilaments, which repeat along the length of the myofibril in sections or units of contraction called sarcomeres.

Detailed explanation-2: -Myofilaments are the three protein filaments of myofibrils in muscle cells. The main proteins involved are myosin, actin, and titin. Myosin and actin are the contractile proteins and titin is an elastic protein.

Detailed explanation-3: –fascicles make up muscles, fibers (cells) make up fascicles, within fiber you have organelle packed with myofilaments and those are called myofibrils, myofibrils contain sarcomeres.

Detailed explanation-4: -Myofibrillar and Sarcomeric Structure. Within myocytes, myofibrils are the most abundant organelle, occupying approximately 50–60% of the cytoplasm. Myofibrils are composed of overlapping thick and thin myofilaments organized into distinct, repeating units called sarcomeres.

Detailed explanation-5: -Myofibrils are composed of smaller structures called myofilaments.