Skeletal System: Bones and Joints Review

Flashcards covering the anatomy of the axial skeleton, skull structures, vertebral regions, and joint classifications based on the lecture transcript.

Axial Skeleton

The division of the skeleton composed of the skull, the vertebral column, and the thoracic cage.

Sutures

Immovable joints that connect the cranial bones; the four principal types are coronal, sagittal, lambdoid, and squamous.

Calvaria

The top of the skull, often removed to view the interior of the skull.

Braincase

The portion of the skull consisting of $8$ cranial bones that enclose the cranial cavity and protect the brain.

Facial Bones

A group of $14$ bones that form the basis of the face and contain cavities for the eyes, nose, and mouth.

Auditory Ossicles

A total of $6$ small bones (three in each middle ear) involved in hearing.

Frontal Bone

Known as the "forehead," it forms the roof of the orbit of the eye and the nasal cavity and contains the frontal sinus.

Supraorbital Foramen

A notch or opening in the superior border of the orbits allowing passage for a blood vessel and nerve to the eyelid and eye.

Glabella

A smooth region of bone located between the two orbits.

Anterior Cranial Fossa

The internal portion of the frontal bone that supports the lobes of the brain.

Parietal Bones

Paired bones forming nearly half of the superior portion of the skull, joined by the sagittal suture.

Zygomatic Arch

A bridge across the side of the skull formed by the joining of the zygomatic process of the temporal bone and the zygomatic bone.

Mandibular Fossa

An oval-shaped fossa on the inferior side of the temporal bone that serves as the attachment site for the mandible.

Petrous Part

A thick, rocky bony ridge of the temporal bone that houses the middle and inner ears.

Mastoid Process

A large, bony inferior projection posterior to the external ear filled with air cells and serving as an attachment for neck muscles.

External Auditory Canal

Also called the external acoustic meatus, it transmits sound waves toward the eardrum within the tympanic part of the temporal bone.

Carotid Canals

Major entry points for blood delivery to the brain located on the inferior side of the petrous part.

Jugular Foramina

Openings that allow the jugular veins to carry the majority of blood away from the brain.

Styloid Process

A projection from the lower petrous part serving as an attachment site for muscles of the tongue, hyoid bone, and pharynx.

Foramen Magnum

The large opening in the occipital bone where the brainstem connects to the spinal cord.

Occipital Condyles

Two rounded projections on either side of the foramen magnum that articulate with the first cervical vertebra to allow nodding.

Sella Turcica

Meaning "Turkish Saddle," this central prominence in the sphenoid bone floor resembles a saddle.

Vomer

A single bone in the midline of the nasal cavity that forms the nasal septum along with the ethmoid bone.

Hyoid Bone

An unpaired, U-shaped bone that does not articulate with any other bone; it supports tongue and neck muscles.

Vertebral Column

The central axis of the skeleton consisting of $26$ individual bones in adults across five regions.

Atlas

The $1^{st}$ cervical vertebra which holds the head.

Axis

The $2^{nd}$ cervical vertebra which allows the head to rotate.

Sternum

The breastbone, part of the thoracic cage that protects vital organs.

True Ribs

Ribs that attach directly to the sternum by cartilage.

Acetabulum

The hip socket or joint of the hip bone where the lower limb attaches.

Synarthrosis

A functional classification for a non-movable joint.

Amphiarthrosis

A functional classification for a slightly movable joint.

Diarthrosis

A functional classification for a freely movable joint.

Synovial Membrane

The inner layer of the joint capsule that lines the cavity and produces viscous, lubricating synovial fluid.

Abduction

Movement of a body part away from the midline.

Adduction

Movement of a body part toward the midline.