What is the primary function of synovial fluid in the joints?

The primary function of synovial fluid in the joints is to reduce friction between articular cartilages. Synovial fluid serves as a lubricant, allowing the smooth movement of bones against each other within a joint. This lubrication is crucial during activities that involve joint movement, such as walking or lifting, as it minimizes wear and tear on the cartilage and helps to prevent damage from friction.

In addition to lubrication, synovial fluid also plays a role in shock absorption and provides nutrients to the avascular articular cartilage. However, its primary and most important function is the reduction of friction, which is vital for maintaining joint health and function. Other options, such as providing structural support or facilitating blood circulation, do not accurately represent the role of synovial fluid in the joint environment.