In addition to supporting the body, what other function does the muscles system serve?

The muscular system plays a vital role in facilitating movement within the body. This function is essential for many everyday activities, such as walking, running, lifting, and even sitting up. Muscles work by contracting and relaxing, which allows the skeleton to move and perform various actions. This movement is not only crucial for physical activity but also integral for bodily functions, including posture maintenance and the movement of substances through organs.

While the other options mention important biological functions, they do not pertain to the muscular system. For instance, absorbing nutrients is a function of the digestive system, circulating blood is primarily the responsibility of the circulatory system, and eliminating waste is related to the excretory system. Thus, the primary function of the muscular system, alongside its role in supporting the body, is indeed to cause movement.