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.

Detailed explanation-2: -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-3: -The irregular bones are: the vertebræ, sacrum, coccyx, temporal, sphenoid, ethmoid, zygomatic, maxilla, mandible, palatine, inferior nasal concha, and hyoid.

Detailed explanation-4: -These irregular bones include the vertebrae, coccyx, sacrum, temporal, ethmoid, sphenoid, zygomatic, mandible, maxilla, inferior nasal concha, palatine, and hyoid. The irregular bones can be affected by infections, trauma, fractures, osteoporosis, and osteomyelitis.

Detailed explanation-5: -The spinal column, a defining synapomorphy shared by nearly all vertebrates, is a moderately flexible series of vertebrae (singular vertebra), each constituting a characteristic irregular bone whose complex structure is composed primarily of bone, and secondarily of hyaline cartilage.