Answer:
In the knee joint attaching muscles to bones.
The ends of bones in a ball and socket joint.
Step-by-step explanation:
Cartilage is a smooth tissue that is present at the ends of two long bones such as knee joint and ball and socket joint. This cartilage is very important because it protects bones from degradation during movement. Between the attachment of two bones, cartilage as well as oil is present in order to reduce friction during movement. So cartilage is very important between two long bones.