The humerus is an example of which bone type?

• A. Short Bones
• B. Irregular Bones
• C. Flat Bones
• D. Long Bones

Answer: (D)

Bone shapes are classified by how long they are in relation to their width. A long bone is longer than it is wide and has a tubular shaft (the diaphysis) with expanded ends (the epiphyses) that form joints. The humerus fits this pattern as the long upper-arm bone extending from shoulder to elbow, with a cylindrical shaft and enlarged ends to articulate with the shoulder and forearm. Short bones are roughly cube-shaped, flat bones are thin and curved, and irregular bones have complex shapes, like the vertebrae. So the humerus is a long bone.