What is the collective term for long fibres that usually join into a tendon at each end and insert into the bones of the skeleton?

The correct answer is based on the understanding of how muscles are structured and function in the body. Muscles consist of long, fibrous structures known as muscle fibers, which are bundled together to form the overall muscle. These muscle fibers contract to create movement and exert force on the skeleton. When a muscle contracts, its fibers pull on the tendons that attach the muscle to the bones, thus facilitating movement.

In contrast, myofibrils are the actual contractile units within muscle fibers, not the collective structure that connects to bones. Tendons themselves are connective tissues that specifically attach muscles to bones, so they do not encompass the entire structure of the muscle fibers. Ligaments, meanwhile, connect bones to other bones at joints and do not relate to the muscular system in the way the question describes. Understanding these distinctions is crucial in identifying the role and structure of muscles in the body.