Final answer:
The central tendon is the point of insertion for the muscle fibers of the diaphragm. It is the shared attachment point where the diaphragm's muscle fibers converge and is similar to an aponeurosis. The diaphragm's muscle fibers have various origins but all insert into the central tendon.
Step-by-step explanation:
The tendon that serves as the point of insertion for all muscle fibers of the diaphragm is known as the central tendon. This tendon is crucial because it is the shared attachment point where the muscle fibers of the diaphragm come together after spreading out and covering a large area. It is similar to an aponeurosis, which is a flat, broad tendon. The diaphragm has several origins, including the xiphoid process of the sternum, the lower six ribs and their cartilages, and the lumbar vertebrae; however, all of these fibers ultimately converge on the central tendon.
The inferior surface of the pericardial sac and the pleural membranes (parietal pleura) fuse onto the central tendon of the diaphragm. This structural arrangement allows the diaphragm to effectively serve as a muscle of respiration, creating a dome that can flatten to facilitate breathing. The collagen in the tissue layers, the mysia, of these muscles also intertwines with the collagen of tendons, which further illustrates how skeletal muscles work in conjunction with tendons and bones to allow movement.