Thoracic cage

Definition

The thoracic cage, also known as the rib cage, is a bony structure that encases and protects the heart, lungs, and other vital organs in the chest. It consists of the sternum, 12 pairs of ribs, and the thoracic vertebrae.

5 Must Know Facts For Your Next Test

1. The thoracic cage plays a crucial role in respiration by allowing expansion and contraction during breathing.
2. It consists of three parts: the sternum (breastbone), ribs, and thoracic vertebrae.
3. The first seven pairs of ribs are called true ribs because they directly attach to the sternum via costal cartilages.
4. The next three pairs (8-10) are known as false ribs; they connect to the sternum indirectly through cartilage.
5. The last two pairs (11-12) are called floating ribs because they do not attach to the sternum at all.

Review Questions

• What are the main components of the thoracic cage?
• How do true ribs differ from false ribs and floating ribs?
• What is the primary function of the thoracic cage during respiration?

Related terms

Sternum: A flat bone located at the center of the chest that forms part of the front of the rib cage.

Costal Cartilage: Bars of hyaline cartilage that connect some ribs to their respective sternums.

Thoracic Vertebrae: The twelve vertebrae located in the middle section of the spine that provide attachment points for each pair of ribs.