1. Some bones can move because they areconnected by movable
joints. Some bones areconnected by immovable joints.2.
Ball-and-socket joints allow free movement.3. Hinge joints allow
movement in only onedirection.
. !liding joints allow movement in differentdirections.". #ivot
joint allows a $art of the body to turnwithout making the $art
attached to it move.%. &artilage is a smooth' tough material
that$rotects the ends of the bones. (t covers theends of the bones
that move. (t serves as acushion between two bones.). Bones that
move are held in $lace byligaments. *igament is a tough material
thatconnects bones together at the joints.
+. ,he synovial fluid serves as a lubricant to$revent wear and
tear of bones.
