Final answer:
The functional classification of joints is based on the amount of movement allowed. Joints can be immovable, partly movable, or movable. Immovable joints don't allow any movement, partly movable joints allow limited movement, and movable joints allow a wide range of movement.
Step-by-step explanation:
The functional classification of joints is based on the amount of movement allowed by the joint. There are three types of joints in the functional classification: immovable, partly movable, and movable joints. Immovable joints allow for no movement, such as the sutures between the bones of the skull. Partly movable joints allow for limited movement, such as the intervertebral discs of the vertebral column. Movable joints, also known as synovial joints, allow for a wide range of movement, such as the ball-and-socket joint of the hip.