Second: cartilages

Cartilage is a connective tissue made of cartilage cells (chondrocytes) in a firm but flexible matrix. It is found:

• at the ends of bones, especially at joints, and between the vertebrae, to protect the bones from wear (corrosion) caused by continuous friction;
• forming parts of the body such as the ear (pinna), the nose and the walls of the trachea (the C-shaped rings that keep the airway open).

• Cartilage has no blood vessels, so its cells obtain food and oxygen by diffusion from the nearby bone cells (and surrounding tissue).
• For this reason, damaged cartilage heals very slowly.