Which proprioceptive structure signals force exerted on a muscle through stretch receptors?

The structure that signals the force exerted on a muscle through stretch receptors is the Golgi Tendon Organs. These specialized proprioceptors are located at the junctions between muscles and tendons and are sensitive to changes in muscle tension. When a muscle contracts, the tension generated is transmitted to the Golgi Tendon Organs.

As the tension increases, these organs become activated and send signals to the central nervous system, providing crucial feedback about the force being exerted. This information is essential for coordinating movements and for reflex mechanisms that protect muscles from excessive tension, thus preventing injury.

In contrast, muscle spindles primarily detect changes in muscle length and the rate of that change, allowing the nervous system to regulate muscle contraction. Joint receptors are involved in sensing the position and movement of joints, while muscular connective tissues support the structure of the muscles but do not play a direct role in signaling muscle force. Therefore, Golgi Tendon Organs are specifically designed to monitor and relay information about the force exerted on muscles.