Synovial is correct. Synovial cavities are present around the joints containing a thin oily synovial fluid that reduces the friction around the joints.Highly movable joints like that of elbow or a knee and a shoulder or hip joint also need lubrication and cushioning to prevent the adjoining bone crushing with each other.
STB Pg- 40.
Fluid-filled cavities within the brain that produce and circulate cerebrospinal fluid.
The cup-shaped socket in the hip bone that articulates with the femur to form the hip joint.
A bony prominence on the humerus, important for the attachment of the deltoid muscle in the upper arm.
Synovial is correct. Synovial cavities are present around the joints containing a thin oily synovial fluid that reduces the friction around the joints.
Highly movable joints like that of elbow or a knee and a shoulder or hip joint also need lubrication and cushioning to prevent the adjoining bone crushing with each other.
STB Pg- 40.