Bones of the Axial Skeleton - BIO210 Lab 6A

Comprehensive vocabulary flashcards covering the bones, sutures, features, and landmarks of the human axial skeleton from BIO210 Lab 6A.

Axial skeleton

The primary division of the human skeleton that consists of the skull, vertebral column, and thoracic cage.

Coronal suture

The cranial joint located between the frontal bone and the anterior borders of the parietal bones.

Sagittal suture

The midline fibrous joint running along the top of the cranium that unites the two parietal bones.

Lambdoid suture

The suture located across the posterior skull that connects the parietal bones with the occipital bone.

Squamous suture

The suture situated on the lateral aspect of the skull that joins the temporal bone to the parietal bone.

Foramen magnum

The large aperture located at the base of the occipital bone through which the spinal cord passes to connect with the brainstem.

Sella turcica

A saddle-shaped depression situated in the central body of the sphenoid bone that houses and protects the pituitary gland.

Crista galli

A prominent, vertical cock's-comb-shaped ridge on the superior midline of the ethmoid bone serving as a cranial attachment site.

Cribriform plate

The horizontal, porous bone section of the ethmoid bone surrounding the crista galli containing olfactory foramina.

Condylar process

The rounded posterior superior projection of the mandibular ramus that articulates with the mandibular fossa of the temporal bone.

Coronoid process of the mandible

The flat, pointed anterior superior projection of the mandibular ramus that serves as an attachment point for temporalis muscle fibers.

Mandibular notch

The broad, curved U-shaped depression separating the coronoid process from the condylar process on the mandibular ramus.

Mental foramina

Paired openings situated on the anterolateral exterior surface of the mandibular body for nerve and blood vessel passage.

Paranasal sinuses

Air-filled mucosal spaces situated within facial and cranial bones including the frontal sinus, sphenoid sinus, ethmoid air cells, and maxillary sinus.

Anterior fontanelle

The large diamond-shaped unossified fibrous membrane located at the junction of the frontal and parietal bones in the fetal/infant skull.

Posterior fontanelle

The small triangular membranous space located at the junction between the sagittal and lambdoid sutures on the fetal/infant skull.

Hyoid bone

A U-shaped bone in the anterior neck that does not articulate with any other bone.

Vertebral column curves

The four natural curvatures of the spine: cervical curvature, thoracic curvature, lumbar curvature, and sacral curvature.

Atlas

The first cervical vertebra ($C1$), which lacks a vertebral body and spinous process, and articulates directly with the occipital condyles of the skull.

Axis

The second cervical vertebra ($C2$), characterized by a vertical tooth-like odontoid process (dens) providing a pivot for skull rotation.

Odontoid process (dens)

A prominent peg-like superior projection arising from the body of the axis ($C2$) vertebra that articulates with the anterior arch of the atlas ($C1$).

Cervical vertebrae

The $7$ vertebrae labeled $C1\text{--}C7$ characterized by transverse foramina in the transverse processes, a small body, and a bifid spinous process.

Thoracic vertebrae

The $12$ vertebrae labeled $T1\text{--}T12$ distinguished by thick large transverse processes, long inferiorly directed spinous processes, round-heart shaped bodies, and round vertebral foramina.

Lumbar vertebrae

The $5$ vertebrae labeled $L1\text{--}L5$ featuring the largest bean-shaped bodies, thick blunt spinous processes, short transverse processes, and triangular vertebral foramina.

Sacrum

A triangular bone formed by the fusion of $5$ sacral vertebrae located inferior to the lumbar spine.

Coccyx

The terminal triangular bone of the vertebral column formed by the fusion of $3\text{--}5$ small coccygeal vertebrae.

True ribs

Ribs $1\text{--}7$; ribs that attach directly to the sternum through their own individual costal cartilages.

False ribs

Ribs $8\text{--}12$; ribs that do not connect directly to the sternum.

Floating ribs

Ribs $11\text{--}12$; a specific subset of false ribs that have no anterior cartilaginous connection to the sternum.

Sternum

The anterior midline chest bone comprising three major anatomical components: the manubrium, body, and xiphoid process.

Costal cartilages

Segments of hyaline cartilage that connect the anterior ends of the ribs to the lateral borders of the sternum.