Which joint type is characterized by a cavity and synovial fluid and is the most freely movable?

Which joint type is characterized by a cavity and synovial fluid and is the most freely movable?

• A. Synovial joint
• B. Fibrous joint
• C. Cartilaginous joint
• D. Hinge joint

Answer: (A)

The key idea is that a synovial joint has a joint cavity filled with synovial fluid, which is what allows the most movement. This cavity sits inside a capsule lined by a synovial membrane that secretes the fluid. The ends of the bones are covered with articular cartilage, and the capsule is reinforced by ligaments. All together, this setup reduces friction, nourishes the cartilage, and lets the joint move freely in multiple directions. Fibrous joints have no cavity and are largely immobile; cartilaginous joints lack a joint cavity and move only a bit; and a hinge joint is a type within the synovial family, not a separate category. So the joint type described is the synovial joint.

The key idea is that a synovial joint has a joint cavity filled with synovial fluid, which is what allows the most movement. This cavity sits inside a capsule lined by a synovial membrane that secretes the fluid. The ends of the bones are covered with articular cartilage, and the capsule is reinforced by ligaments. All together, this setup reduces friction, nourishes the cartilage, and lets the joint move freely in multiple directions. Fibrous joints have no cavity and are largely immobile; cartilaginous joints lack a joint cavity and move only a bit; and a hinge joint is a type within the synovial family, not a separate category. So the joint type described is the synovial joint.