Answer
Myofibrils are groups of myofilaments that contract. Myofilaments can be either thin (actin) or thick (myosin) filaments that control muscle striations and contractions. Muscle fibers contain collections of myofibrils that are divided into sarcomeres, which are contractile.
Work Step by Step
Myofibrils are groups of myofilaments that contract. Myofilaments can be either thin (actin) or thick (myosin) filaments that control muscle striations and contractions. Muscle fibers contain collections of myofibrils that are divided into sarcomeres, which are contractile.