Costal cartilage is a type of flexible connective tissue that connects the ribs to the sternum (breastbone). It allows the ribcage to expand and contract during breathing, providing flexibility and support. This cartilage is made primarily of collagen and elastin fibers, which give it strength and elasticity. In addition to its role in the respiratory system, costal cartilage helps protect vital organs in the thoracic cavity. It also contributes to the overall structure of the ribcage, ensuring that the ribs maintain their shape while allowing for movement.