Chap. 7 Axial Skeleton-Lab Review

Identify the typical number of vertebrae that fuse during development to form the coccyx.

3-5

Name the number of vertebrae that fuse together to form the sacrum.

5

What is the name of the first cervical vertebra?

Atlas

Which vertebra lacks both a body and spinous process?

Atlas

Identify the articulation site that allows us to rotate our head, e.g. shaking the head "no".

Atlas - axis

Identify the region of the sacrum that articulates with the hip bone.

Auricular surface

Identify the tailbone.

Coccyx

Which landmark is composed of fused spinous processes?

Median sacral crest

Identify the articulation site that allows us to nod our head "yes".

Occipital bone - atlas

Identify the region of the skull that articulates with the atlas.

Occipital condyles

Identify the bony posterior wall of the pelvis.

Sacrum

The orbital rim is strong, composed of thick, protective bone. But the very thin medial wall and floor of the orbit were literally blown out by the intact eyeball itself when the boxer was struck with such a forceful blow. Which bones compose the orbital rim?

The maxilla and zygomatic bone both articulate with the frontal bone to form the orbital rim.

Surrounding the orbits are the four paranasal sinuses. What are these structures?

The paranasal sinuses are air-filled chambers lined with mucus-producing epithelium that open into the nasal cavities.

What is the name of the second cervical vertebra?

axis

The maxilla also frequently sustains fractures from blunt trauma to the face. Which structures support and house the upper teeth in this bone?

the alveolar process

The young boxer has sustained a "blowout" fracture of his left orbital complex. The orbit that contains the eye is formed by seven facial bones. Which skull bone forms the roof of the orbit?

the frontal bone