anat 200: axial skeleton

The Axial Skeleton and Appendicular Skeleton

The skeletal system is composed of:

cranium (8) and facial bones (14)

The Skull is made up of:

hyoid bone and auditory ossicles

These are the associated bones of the skull

Hyoid Bone

Bone that is not attached to any other bones (non-articulating), but it is located in the anterior neck and serves as a attachment site for muscles of the tongue and pharynx

Auditory ossicles

This bone (s) consist of the malleus, incus, and stapes bones

Sternum (1) and 24 Ribs

The thoracic cage consists of:

Vertebrae (24), Sacrum (1) and Coccyx (1)

The Vertebral column consists of the:

Supports and protects internal organs

The function of the axial skeleton is that it:

Skull

This structure houses special sensory organs
(e.g., ear, tongue, eyeball)

The Vertebral Column and Ribs

These structures provide extensive attachment for muscles moving the head, neck, trunk and limbs.

Thoracic cage

This structure performs movements during respiration

Cranial Bone: Frontal bone

Skull Bone on Forehead \= \________

Cranial Bone: Parietal bone (2)

Side walls of your cranium and they are in pairs \__________

Temporal bone (2)

When you have a headache, you massage your "temples" this is known as the \__________ located below (inferior) to parietal bone

Cranial Bone: Occipital Bone

Think eyes in the back of my head for this bone \_________ *pay close attention to "back of my head"

Sphenoid Bone

Bone that joins all of the bones of the cranium together, spans entire width of cranium when seen from an inferior view and not in a pair

Ethmoid bone

When seen from the anterior view, it is enclosed in the eye behind the nasal bones. Located

Ethan's Fried Spanish Pasta Tempted Octavia

Mnemonic for memorizing Cranial bones (front to back)
ethmoid, frontal, sphenoid, parietal, temporal, occipital

Facial Bone: Mandible (1)

Think about your jawline and that is where the \_________ is

Maxilla

Located superior to the mandible and inferior to the Nasal bone and forms the upper jaw of your facial bone

Facial Bone: Vomer (1)

forms the inferior portion of the nasal septum

Nasal Bone

Make up the bridge of the nose

Lacrimal Bone

small fragile bone making up part of the front inner walls of each eye socket and providing room for the passage of the lacrimal ducts. Think where the tear ducts happen.

palatine bone

either of two irregularly shaped bones that form the back of the hard palate and helps to form the nasal cavity and the floor of the orbits

Zygomatic bone

the arch of bone beneath the eye that forms the prominence of the cheek. Also known as the cheek bone

coronal suture

the suture between the parietal and frontal bones of the skull.

Lambdoid Suture

between parietal bones and occipital bone

Squamous Suture (Skull)

Between parietal and temporal bones

superior orbital fissure

Located in the skull, between the greater and lesser wings of the sphenoid bone. It is located in the front of the skull, above the eye socket (orbit).

saggital suture

separates the left and right parietal bone

optic canal

Small opening located in the skull, near the superior orbital fissure, that allows the optic nerve and ophthalmic artery to pass through the skull and into the orbit (eye socket).

zygomatic arch

bridge of bone extending from the temporal bone at the side of the head around to the maxilla (upper jawbone) in front and including the zygomatic (cheek) bone.

occipital condyles (2)

Rounded projections on located laterally on both sides of the foramen magnum that articulate with the first cervical vertebra (atlas)

foramen magnum

opening of the occipital bone through which the spinal cord passes

carotid canal of temporal bone

for internal carotid artery

jugular foramen

\____________ is a large opening located in the base of the skull, on either side of the foramen magnum. It is formed by the union of the temporal bone and the occipital bone.
A passage for several important structures including the jugular vein.

Mastoid Process, Mandibular fossa, External acoustic meatus

Know and label the Components of the temporal bone from openstax textbook

mastoid process of temporal bone

A bony protuberance located behind the ear that serves as an attachment site for muscles of the neck and head.

mandibular fossa of temporal bone

the depression in the temporal bone into which the condyle of the mandible fits

external acoustic meatus

An opening in the temporal bone that leads to the ear canal and conducts sound waves to the eardrum.

Parts of the Mandible temporomandibular joint (TMJ)

the joint between the temporal bone and the mandible

Parts of the Mandible: ramus of mandible

vertical portion of the lower jaw that communicates with the skull

Coronoid Process

a flattened triangular bony process of the ramus of the mandible. It is usually directed upwards. Helps close the jaw.

mandibular condyle of the mandible

articulates with the mandibular fossa of the temporal bone. Helps rotate the jaw.

Skull Cavities

Cranial cavity, Orbits, Nasal cavity, Oral cavity, , Paranasal Sinuses

paranasal sinuses

air cavities within the cranial bones that open into the nasal cavities

Orbit (eyeball)

the bony socket that houses the eyeball and muscles that move the eyeball or open the upper eyelid.

Parts of the Cranial Cavity

Frontal bone, Ethmoid bone, Occipital bone, parietal bone, Sphenoid bone, temporal bone

parts of orbital region

Lacrimal bone, frontal bone, ethmoid bone, sephnoid bone , zygomatic bone, palatine bone, nasal bone, maxillary

Cranial cavity

Cavity contains the brain

frontal, sphenoid, ethmoid, maxillary

What are the 4 paranasal sinuses?

Oral cavity

The part of the mouth behind the gums and teeth that is bounded above by the hard and soft palates and below by the tongue and by the mucous membrane connecting it with the inner part of the mandible.

Infant Skull Anatomy: Anterior Fontanelle and Posterior Fontanelle

Part of the Infant Skull: diamond shaped depression

trangular shaped depression (back of skull)

Function: Both these structures help the development of the baby's skull during the first year of life...

Infant Skull Anatomy: Metopic suture

suture located between the right & left frontal, normally fuses together before birth

Primary Curvature

These are also also called kyphotic curves, are curves that were present during fetal development.

Convex curve outward towards backside.

is the primary curvature primarily concave or convex?

They include the thoracic curvature (T1-T12), and the sacral bone

What is included in the primary curvature?

also called lordotic curves, are curves that slowly begin form postpartum (after the baby's birth).

These curves are concave, curving inwardly toward the front of the body.

Are seconderary curves concave or convex?

They include the cervical curvature (C1-C7), as well as the lumbar curvature (L1-L5).

What parts of the vertebral column are included in the secondary curvature?

Vertebral Column Bones

7 cervical, 12 thoracic, 5 lumbar, 5 sacral, 4 coccygeal

vertebral body

Transfers weight along the spine
Forms anterior margin of each vertebral foramen

pedicle of vertebrae

Portion of the neural arch just posterior to the body and anterior to the lamina. Role in protecting the spinal cord.

vertebral foramen

canal through which spinal cord passes. Provides a pathway for transferring nutrients and waste products to and from the spinal cord.

Lamina of vertebra

\_______________ forms part of the posterior roof of the vertebral foramen. Also protects the posterior or back end of spinal cord.

superior and inferior articular processes

A \_________________ process extends or faces upward, and an \__________________process faces or projects downward on each side of a vertebrae.

Spinous process of vertebra

Projects posteriorly at the midline of the back. Serves as a muscle and ligament attachment sites

Transverse process

two lateral projections from the vertebral arch/foramen. They help support the muscles and attachments to the spine as well.

intervertebral discs

fibrocartilage pads that separate and cushion the vertebrae. Also provide padding between vertebrae during weight bearing.

intervertebral joints (same as discs)

between adjacent vertebral bodies of spinal column

zygapophyseal joints

The joints between two articular processes of vertebra are termed:

Vertebral canal

Houses the spinal cord and meninges. Serves as the bony protection and passageway for the spinal cord down the back.

annulus fibrosus

Outer Part of intervertebral disc. Surrounds the nucleus pulposus with a collar composed of collagen and fibrocartilage

Nucleus pulposus

Inner/Central part of intervertebral disc. The soft, fibrocartilaginous, central portion of intervertebral disk

cervical vertebrae

C1-C7; first set of seven bones, forming the neck. Most have a bifid spinal process

C1

atlas; supports the skull on top of the vertebral column

F; it has an anterior and posterior arch

The C1 has a spinous process. T or F?

atlanto-occipital joint

The synovial joint between occipital condyles & C1
(allows flexion of head up and down)

True

The transverse processes of C1 are longer than others.
T or F

C2

axis; serves as the axis for rotation when turning the head toward the right or left. The

Dens; (odontoid process), a bony projection that extends upward from the vertebral body.

C2 is easily differentiated from other vertebra because of the presence of the \________

Atlanto-axial joint

synovial joint between C1 & C2 (allows head to turn side-to-side)

C3-C6 vertebrae

Which Cervical vertebrae have short spinous processes

C7

(vertebra prominens): landmark for counting vertebrae

transverse foramen of cervical vertebrae

allows passage of vertebral artery going up to supply the brain

thoracic vertebrae

the second set of 12 vertebrae; form the outward curve of the spine and are known as T1 through T12.

True

The bodies of the thoracic vertebrae are larger than those of cervical vertebrae. T or F

the spinous process, which is long and projects downward to overlap the next inferior vertebra.

What distinguishes the thoracic vertebrae from others?

Superior and inferor Coastal facets (Thoracic)

Only in the thoracic vertebrae. These are small, smooth spots for rib attachment.

lumbar vertebrae

L1-L5; lower back

carry the greatest amount of body weight

Lumbar vetrebrae are unique because they:

F; both are short...

Lumbar vertebrae have SHORT transverse processes and LONG spinous process. T or F?

True

Lumbar vertebrae have large articular processes; t or f

Costovertebral joint

two synovial joints between thoracic vertebra and associated rib (allow the rib to move slightly during
respiration)

sacrum and coccyx

bottom of spine

sacral promontory

anterior lip of the superior base of the sacrum

sacral canal

continuation of the vertebral canal in the sacrum

sacral foramina of sacrum; anterior and posterior branches of the spinal nerves to exit the sacrum.

The anterior and posterior surfaces of the sacrum have a series of paired openings/holes called the: \____________; which allow for the \___________________________

superior articular process of sacrum

articulates with L5

The apex of the coccyx

extreme distal tip of the last coccygeal segment.