Identify one function of synovial fluid.

Synovial fluid plays a crucial role in joint health, primarily by lubricating and nourishing joint surfaces. This viscous fluid is found in synovial joints, which are the most movable joints in the body, such as the knees, hips, and shoulders. By reducing friction between the articular cartilages of these joints, synovial fluid allows for smooth movements during activities such as walking, running, and lifting.

Additionally, synovial fluid contains various nutrients and enzymes that help maintain the health of the cartilage within the joint, ensuring that it remains healthy and can effectively absorb shock during physical activity. The nourishment provided by synovial fluid is vital for the metabolic processes of the cartilage, which itself does not have a direct blood supply.

In contrast, while other bodily fluids serve specific functions, they do not relate directly to the duties of synovial fluid regarding joint lubrication and nourishment. For instance, the protection of nerve endings and the transportation of oxygen are functions performed by different systems within the body, specifically the nervous and circulatory systems, respectively.