the flat bone that forms the ventral (front) support of the ribs is the:

The adult vertebrae are further divided into the 7 cervical vertebrae, 12 thoracic vertebrae, and 5 lumbar vertebrae (Figure 4).įigure 4. (a) The vertebral column consists of seven cervical vertebrae (C1–7) twelve thoracic vertebrae (Th1–12), five lumbar vertebrae (L1–5), the os sacrum, and the coccyx. We begin life with approximately 33 vertebrae, but as we grow, several vertebrae fuse together. Around the age of 70, the sacrum and the coccyx may fuse together. The coccyx is typically 3–4 vertebrae that fuse into one. In the adult, the sacrum is typically composed of five vertebrae that fuse into one.

The adult vertebral column comprises 26 bones: the 24 vertebrae, the sacrum, and the coccyx bones. The vertebral column, or spinal column, surrounds and protects the spinal cord, supports the head, and acts as an attachment point for the ribs and muscles of the back and neck.

In animals with teeth, the mandible brings the surfaces of the teeth in contact with the maxillary teeth. The mandible controls the opening to the airway and gut. The mandible articulates with the base of the skull. It acts as a movable base for the tongue and is connected to muscles of the jaw, larynx, and tongue. The hyoid bone lies below the mandible in the front of the neck. The facial bones of the skull form the face and provide cavities for the eyes, nose, and mouth.Īlthough it is not found in the skull, the hyoid bone is considered a component of the axial skeleton. Figure 3. The cranial bones, including the frontal, parietal, and sphenoid bones, cover the top of the head.

The flat bone that forms the ventral (front) support of the ribs is the: