Final answer:
Articular cartilage and synovial fluid provide cushioning in a synovial joint, with additional structures like menisci offering extra support and shock absorption.
Step-by-step explanation:
Extra cushioning and distribution of weight in a synovial joint are primarily provided by the articular cartilage and the synovial fluid. The articular cartilage is a smooth, slippery tissue that covers the ends of bones in a synovial joint, reducing friction and acting as a shock absorber.
In addition to the articular cartilage, the synovial fluid in the joint cavity lubricates the joint, further decreasing friction and providing further cushioning. Some synovial joints also include additional structures such as an articular disc or meniscus, which offer extra cushioning and stability.