What is unique about the true ribs?

True ribs are unique in that their costal cartilage articulates directly with the sternum. This direct connection is what distinguishes true ribs from false ribs, which do not attach directly to the sternum through cartilage. True ribs, specifically ribs one through seven, have individual costal cartilages that provide a direct anterior connection to the sternum, allowing for better stabilization during respiration and movement.

The structure and classification of ribs are significant in understanding their function and anatomy. Options regarding the angle of the bodies of the ribs, facets on the heads, and articulation with demifacets pertain more to characteristics of certain ribs and their interaction with the vertebrae, but do not define what makes true ribs unique in the context of their connection to the sternum. The direct articulation of true ribs with the sternum is fundamental to their role in the thoracic structure and function.