What type of cartilage covers the articular surfaces of bones in joints?

• A. Hyaline cartilage
• B. Fibrocartilage
• C. Elastic cartilage
• D. Dense regular connective tissue

Answer: (A)

The surface of joints is covered by a smooth, glassy cartilage that provides a nearly frictionless interface and helps absorb and distribute loads as bones move. This ideal joint surface is hyaline cartilage. It has a matrix rich in type II collagen and proteoglycans, which gives it that slick, low-friction quality while still being able to cushion repetitive compressive forces.

Fibrocartilage, while very strong and good at resisting shear and compression (as in the menisci of the knee or intervertebral discs), is not the regular articular surface because it isn’t as smooth or slippery as hyaline cartilage. Elastic cartilage contains elastic fibers and is built for shape and flexibility (like in the ear and epiglottis), not for the constant, smooth gliding of joints. Dense regular connective tissue isn’t cartilage at all—it’s the tissue form of tendons and ligaments, which connect bone to bone or bone to muscle, not the joint’s articular surface.