Synovial joints are joint that join bones with fluid filled cartilage cavity called synovial cavity, this have the space that contain the synovial fluid. The joint capsule is made up of outer layer, articular capsule that keep the bone together, and inner layer, the synovial membrane that seals the synovial fluid. The bones of synovial joint are covered with hyaline cartilage layer which line the epipysises of the joint end bone. The articular cartilage help to reduce shock and ease movement. The types of synovial joints are pivot, hinge, saddle,condyloid, plane, ball and socket joints. The synovial joints have ligaments and blood vessels.
A space between the two bones of the synovial joint is called the joint cavity. It allows the synovial joints to move freely.The layer of hyaline cartilage covers the bones of the synovial joints. This is called articular cartilage. It forms a slippery surface to cover the bones. Due to the presence of cartilage, the friction is reduced between bones of the joints during movement.
Synovial joints may also have accessory ligaments present outside or within the articular capsule of the joints. Nerve endings are present in the articular capsule and the related ligaments of these joints. Similarly, blood vessels enter the ligaments and articular capsule of these joints.
I believe it is a. Birds typically migrate in the wintertime to escape harsher climates to places that have more food. Also, some birds migrate to certain places when they are about to start their nesting and breeding seasons.
I don't know if they might be tricking you or something but I believe the only level of organization found in the human heart is: organ. HOPE IT HELPED! :)