Rib

Long bone in vertebrates that protects vital respiratory and cardiovascular organs

In vertebrate anatomy, ribs (Latin: costae) are the long curved bones which form the rib cage, part of the axial skeleton. In most tetrapods, ribs surround the thoracic cavity, enabling the lungs to expand and thus facilitate breathing by expanding the thoracic cavity. They serve to protect the lungs, heart, and other vital organs of the thorax.

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