Endochondral bone that is intersegmental and rod-shaped, forming in the peritoneal membrane and attached to the vertebral parapophyses. Ribs protect and support internal organs.[TAO], Endochondral, rodlike element that articulates with the transverse process and parapophysis (double-headed rib), or with the transverse process only (single-headed rib); it extends into the body wall and provides a site for muscle attachment.[AAO]

They protect and support internal organs and enable lungs to expand by expanding the chest.

uberon

dorsal rib, pleural rib, ribs

costal

UBERON:0002228

In most vertebrates, ribs surround the chest. In some species, especially snakes, ribs may provide support and protection for the entire body

• serratus ventralis
• intercostal muscle
• pectoralis minor
• abdominal external oblique muscle

• joint of rib

• sternum

• intercostal muscle
• abdominal internal oblique muscle

• rib pre-cartilage condensation
• rib cartilage element

• intercostal space

• costal cartilage
• proximal segment of rib
• distal segment of rib