The human skull is classified as which type of bone?

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

Answer: (A)

The main idea here is bone shape. Bones are grouped as flat, long, short, or irregular based on their overall outline and typical function. The bones that form the skull are flat bones. They are thin, broad plates that protect the brain and provide broad surfaces for muscle and membrane attachments. In the skull, these flat bones usually have a sandwich-like structure with an outer and inner compact layer and a middle spongy layer called diploe, which helps keep them strong yet lightweight. This contrasts with long bones, which are tall and bulky and have a hollow cavity, short bones that are cube-like in shape, and irregular bones that have complex shapes like the vertebrae. So, because of their plate-like, protective design, the skull bones are classified as flat bones.