ANATOMY

Detailed explanation-1: -They are primarily spongy bone that is covered with a thin layer of compact bone . The vertebrae and some of the bones in the skull are irregular bones . All bones have surface markings and characteristics that make a specific bone unique.

Detailed explanation-2: -Irregular bones in human skeleton. (shown in red). The irregular bones are: the vertebrae, sacrum, coccyx, temporal, sphenoid, ethmoid, zygomatic, maxilla, mandible, palatine, inferior nasal concha, and hyoid.

Detailed explanation-3: -Irregular bones vary in shape and structure and therefore do not fit into any other category (flat, short, long, or sesamoid). They often have a fairly complex shape, which helps protect internal organs. For example, the vertebrae, irregular bones of the vertebral column, protect the spinal cord.

Detailed explanation-4: -Answer and Explanation: The irregular bones are literally found all over the body including the bones of the spinal column called vertebrae. The sacrum and coccyx are also examples of irregular bones. The cranial bones, ethmoid and sphenoid, can be classified as irregular bones.