Rib
Ribs are classed as flat bones which usually have a protective role in the body. Humans have 24 ribs, in 12 pairs. All are attached at the back to the thoracic vertebrae, and are numbered from 1–12 according to the vertebrae they attach to. The first rib is attached to thoracic vertebra 1 (T1). At the front of the body most of the ribs are joined by costal cartilages to the sternum. The ribs connect to the vertebrae with two joints, the costovertebral joints.
Limb (anatomy)
A limb (from the Old English "lim"), or extremity, is a jointed, or prehensile (as octopus arms or new world monkey tails), appendage of the human or other animal body. In the human body, the upper and lower limbs are commonly called the arms and the legs, respectively. Arms and legs are connected to torso or trunk.