Thoracic cage

Definition

The thoracic cage is the bony structure surrounding the chest cavity, composed of the ribs, thoracic vertebrae, and sternum. It serves to protect vital organs such as the heart and lungs and supports respiratory function.

5 Must Know Facts For Your Next Test

1. The thoracic cage consists of 12 pairs of ribs.
2. The sternum, or breastbone, is a flat bone located in the center of the chest.
3. The first seven pairs of ribs are known as true ribs because they directly connect to the sternum via costal cartilages.
4. Ribs 8-10 are called false ribs because they connect to the sternum indirectly through cartilage that joins with the cartilage of rib 7.
5. Ribs 11 and 12 are referred to as floating ribs since they do not attach to the sternum at all.

Review Questions

• How many pairs of ribs make up the thoracic cage?
• What distinguishes true ribs from false and floating ribs?
• Which bones constitute the thoracic cage?

Related terms

sternum: A flat bone located at the front center of the chest, part of the thoracic cage.

costal cartilage: Hyaline cartilage that connects ribs to the sternum.

thoracic vertebrae: The twelve vertebrae in the middle section of the vertebral column that articulate with rib pairs.