Lab 2: Axial Skeleton

Identify the location of the sphenoid bone. Hint 1. Determine whether the sphenoid bone is a facial bone or part of the cranium.

Floor of the skull The sphenoid bone spans the width of the floor of the skull.

Nerves and blood vessels pass through the _____ to reach the chin. Hint 1. Foramina is the plural of foramen, which is a hole in a bone

Mental foramina The mental foramina allow blood vessels and nerves to pass to the skin of the chin.

Identify the landmark that is not part of the sphenoid bone. Hint 1. This foramen together with the foramen ovale are passages for 2 branches of the trigeminal nerve.

Olfactory foramina The olfactory foramina are found in the cribriform plate of the ethmoid bone, not the sphenoid bone.

Identify the articulation site for a tubercle of a rib Hint 1. The tubercle of a rib is a bony bump found distal to the head and neck.

Transverse costal facet The transverse costal facet is a slight depression found on the transverse process of a thoracic vertebra. It contacts the tubercle of a rib as the rib extends laterally.

What bone forms part of the nasal septum?

Vomer The vomer is a thin bone in the nasal cavity forming part of the nasal septum

The sella turcica is best described as Hint 1. The sella turcica houses the pituitary gland

A depression The sella turcica is a depression in the central region of the sphenoid bone. It houses the pituitary gland

Individual vertebrae articulate with each other forming the vertebral column. Identify the part of a vertebra that articulates immediately with the vertebra below it Hint 1. Consider the many projections that are found on this bone and their locations.

Inferior articular processes The inferior articular processes contact the superior articular process of the vertebra below it, forming a moveable synovial joint.

The tiny holes in the cribriform plate are:

olfactory foramina These foramina allow the olfactory nerve to pass from the nsal cavity to the brain.

How many vertebrae comprise the thoracic region of the spine? Hint 1. Bones of the thoracic region

12 Human beings have 12 total thoracic vertebrae. These vertebrae articulate with the ribs (humans have a total of 12 pairs of ribs)

How many bones make up the nasal septum? Hint 1. The nasal septum divides the nasal cavity into a right and left half.

2 The nasal septum is composed of the perpendicular plate of the ethmoid and the vomer.

How many ribs make up the rib cage? Hint 1. Think about the region of the vertebral column that articulates with the ribs

24 The rib cage is composed of 12 pairs of ribs, 24 ribs in total. The 12 pairs of ribs articulate with the thoracic vertebrae posteriorly.

Identify the typical number of vertebrae that fuse during development to form the coccyx Hint 1. The number of vertebrae that fuse to form the coccyx can differ from the number of vertebrae that fuse to form the sacrum

3-5 The coccyx is formed by 3-5 vertebrae fusing together during development

How many pairs of ribs are considered false ribs? Hint 1. Determine the number of ribs that do not articulate directly with the sternum.

5 5 pairs of ribs are false ribs. False ribs either attach to the sternum indirectly by articulating with the costal cartilage of the rib above it, or do not attach to the sternum at all

Name the number of vertebrae that fuse together to form the sacrum. Hint 1. Recall the number of vertebrae found in the sacral region during fetal development.

5 During development, individual vertebrae compose the entire vertebral column. Five bones fuse together to form the sacrum

How many lumbar vertebrae are in the vertebral column? Hint 1. opened hintThe lumbar region is a smaller region than the cervical and thoracic regions.

5 Five lumbar vertebrae make up the lower back region

How many pairs of ribs articulate directly with the sternum? Hint 1. Determine the number of true ribs and false ribs.

7 There are 7 pairs of true ribs in the human body. True ribs articulate directly with the sternum

How many pairs of ribs articulate directly with the sternum? Hint 1. Determine the number of true ribs and false ribs

7 There are 7 pairs of true ribs in the human body. True ribs articulate directly with the sternum.

Identify the best description of the mandibular condyle Hint 1. What bone contains the mandibular condyle?

A projection on the mandible The mandibular condyle is the projection on the mandible that helps form the temporomandibular joint.

Identify the best description of the mandibular fossa. Hint 1. Recall which bone has the mandibular fossa and its contour.

A shallow depression The term fossa refers to a landmark that has a concave surface

Which vertebra lacks both a body and spinous process? Which vertebra lacks both a body and spinous process?AxisAtlas

Atlas

What is the name of the first cervical vertebra? Hint 1. This bone supports and carries the skull at the top of the vertebral column.

Atlas The atlas is essentially a ring of bone. Its structure is highly specialized to articulate with the skull.

Identify the articulation site that allows us to rotate our head, e.g. shaking the head "no" Hint 1. A specialized landmark makes this articulation site particularly flexible.

Atlas - axis The prominent projection known as dens on the axis forms a pivot joint with the atlas, allowing the atlas to rotate around the axis. The axis is a very sensible name for C2 since it serves as a central axis for rotation of the atlas.

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

Auricular surface The auricular surface articulates iwth the sacrum, forming the sacroiliac joint

What is the name of the second cervical vertebra? Hint 1. This bone has a specialized feature that gives it a specialized function.

Axis C2 is known as the axis. It has a bony projection called the odontoid process that articulates with C1. C1 can pivot around C2, allowing us to rotate our head/shake head "no".

Identify the central portion of the sternum Hint 1. This region of the sternum is the largest

Body The body of the sternum is the largest region, occupying the space between the manubrium and the xiphoid process.

Which part of a vertebra is known as the centrum? Hint 1. Consider what area of this bone is structurally best suited to bear weight.

Body The disk shaped bodies of vertebrae are stable and stackable. Most weight is distributed in this region.

Identify the general location of the zygomatic arch Hint 1. Recall which 2 bones form the zygomatic arch.

Cheek The zygomatic arch is a bony bridge formed between the zygomatic and temporal bones. It contributes to the prominence of the cheek.

Identify the tailbone. Hint 1. The tailbone is described as a nearly useless bone.

Coccyx The coccyx is the tailbone. It articulates with the vertebral column inferior to the sacrum.

Identify the recessed area surrounding the crista galli.

Cribriform plates The paired cribriform plates surround the crista galli and contain the tiny olfactory foramina.

Identify the landmark that projects superiorly into the floor of the skull and serves as a site of attachment for the meninges.

Crista galli The crista galli is a small plate-like projection visible in the anterior floor of the skull. The dura mater anchors to the crista galli, stabilizing the meninges and brain within the cranial cavity

Identify the articulation site for the head of a rib. Hint 1. The head of a rib occupies an area between 2 vertebrae.

Demi-facet The demi-facets are located on the lateral posterior regions of the bodies of the thoracic vertebral. Together, the superior demi-facet of one vertebra and the inferior demi-facet of the neighboring vertebra create a facet where the head of a rib articulates with the vertebral column.

Which of the following characteristics do not belong to the lumbar region? Hint 1. The overall size of the vertebrae increase progressively from the top of the vertebral column to the bottom of the column

Elongated spinous process An elongated spinous process is characteristic of the thoracic region.

Which of the following bones is not a facial bone?

Ethmoid The ethmoid bone forms the area of the cranium between the nasal cavity and the orbits.

Identify the hole that marks the opening of the ear canal on the superficial surface of the skull. Hint 1. Think about the location of this bone, and the structure conveyed by this canal.

External acoustic meatus The external acoustic meatus is the obvious hole in the temporal bone. This opening conveys sound waves to the eardrum

The ethmoid bone is a facial bone.

False The ethmoid bone is part of the cranium

The lumbar vertebrae are part of the appendicular skeleton Hint 1. The skeleton is divided into 2 main parts: the appendicular skeleton and axial skeleton

False The lumbar vertebrae are part of the vertebral column, which is part of the axial skeleton

The lumbar vertebrae are roughly the same size as vertebrae from the rest of the vertebral column Hint 1. Is there a size difference between a cervical vertebra and lumbar vertebra?

False The overall size of the vertebrae increase from the top of the vertebral column to the bottom.

The ethmoid bone forms the inferior portion of the nasal septum.

False The perpendicular plate of the ethmoid bone forms the superior part of the nasal septum.

Name the opening in the occipital bone through which the spinal cord passes. Hint 1. This is a very large, conspicuous hole

Foramen magnum The foramen magnum is the opening through which the spinal cord passes.

What part of the nasal cavity is formed by the nasal septum? Hint 1. Recall the nasal septum is found in a sagittal plane.

Forms the medial wall of the nasal cavity. The nasal septum divides the nasal cavity in half on midline, thereby forming the medial wall of the nasal cavity on both the right and left sides.

Which of the following bones is unpaired?

Frontal (There is only one frontal bone. It forms the anterior portion of the cranium (the forehead region).

Identify the part of a rib that articulates in the demi-facets of the thoracic vertebra. Hint 1. The proximal end of the rib articulates with the vertebral column.

Head The head of a rib articulates in a region between 2 thoracic vertebrae, contacting the inferior demi-facet of the top vertebra, and the superior demi-facet of the bottom vertebra.

Name the type of connective tissue that anchors the ribs onto the sternum. Hint 1. This tissue is known as costal cartilage.

Hyaline cartilage The costal cartilage that anchors the ribs onto the sternum is hyaline cartilage. Hyaline cartilage is the most common type of cartilage in the body.

Identify the location of the ethmoid bone.

In between the orbits The ethmoid bone is a single bone with a complex shape. The top of this bone projects up into the floor of the cranium. The middle of this bone spans the distance between the orbits, and the lowest most portion forms the superior part of the nasal septum.

Where is the mandibular fossa located? Hint 1. The mandibular fossa is located near other major landmarks of the temporal bone.

Inferior surface of the zygomatic process The mandibular fossa is located immediately anterior to the external auditory meatus, just inferior to the proximal part of the zygomatic process.

Identify the small hole on the maxillary bone located below the orbit. Hint 1. This opening permits a nerve and artery to reach the face.

Infraorbital foramen The conspicuous infraorbital foramen is located below the orbit on the maxillary bone, as its name indicates

Which of the following structures would not be found within a vertebral foramen? Hint 1. The vertebral foramen align and form the vertebral canal.

Intervertebral discs The intervertebral discs are located in between the vertebral bodies. They form a symphysis with the bodies and act as a shock absorber.

Identify the small facial bones found in the medial wall of the orbit.

Lacrimal The lacrimal bone along with the sphenoid, ethmoid, and frontal bones make up the medial wall of the orbit

Which bone is NOT considered to be part of the cranium?

Lacrimal bone (The lacrimal bone is a tiny bone found in the medial portion of the orbit. It is a facial bone, not part of the cranium.)

Identify the large suture on the posterior surface of the skull at the border of the occipital bone. Hint 1. A suture is a fibrous joint formed between skull bones.

Lambdoid The lambdoid suture is found between the occipital bone and the parietal and temporal bones.

Which of these regions of the vertebral column would be most accessible from a posterior surgical approach?

Lamina

Identify the region of the sphenoid bone that contains the optic canal. Hint 1. The optic canal is a continuous passageway between the orbit of the eye and the inside of the skull

Lesser wings The optic canals are passageways found in the lesser wings. They serve as a passageway for the optic nerve running from the eyeball to the optic chiasma.

Identify the region of the mandible that forms part of the temporomandibular joint. Hint 1. Recall the region of the mandible that articulates with the skull.

Mandibular condyle The mandibular condyle is a knoblike superior projection. It articulates with the mandibular fossa of the temporal bone to form the temporomandibular joint.

Which region of the mandible articulates with the cranium? Hint 1. This region helps to form the temporomandibular joint

Mandibular condyle The mandibular condyle of the mandible is a knob like projection that articulates with the mandibular fossa of the temporal bone.

Which landmark is not visible from an anterior view? Hint 1. The mandible forms part of the jaw.

Mandibular foramina The mandibular foramina are on the medial side of each ramus.

Identify the region of the temporal bone that articulates with the lower jaw. Hint 1. This region is found anterior to the external auditory meatus.

Mandibular fossa The mandibular fossa is a shallow depression of the temporal bone in which the mandibular condyle of the mandible articulates, forming the temporomandibular joint.

Identify the region of the temporal bone that articulates with the mandible. Hint 1. Think about the contour of this region of the temporal bone

Mandibular fossa The word fossa indicates that this landmark is a depression. The mandibular fossa of the temporal bone forms the socket in which the mandibular condyle of the mandible articulates, forming the temporomandibular joint.

Name the U shaped border found between the mandibular condyle and the coronoid process. Hint 1. This area forms the superior border of the mandibular ramus

Mandibular notch The mandibular notch is the name of the U shaped border found between the mandibular condyle and the coronoid process.

The region of the mandible that anchors the coronoid process is the:

Mandibular ramus The mandibular ramus anchors the two processes

Identify the shield shaped top of the sternum. Hint 1. This region is also described as having the shape of the knot on a neck tie.

Manubrium The manubrium is the superior most region of the sternum. It articulates with both the clavicle and the first rib.

Which facial bones fuse to form the upper jaw?

Maxillary The fused maxillary bones are known as the maxilla, and form the upper jaw and part of the palate.

Which surface of the maxillary bones fuse together? Hint 1. The maxillary bones form the upper jaw.

Medial The medial surfaces of the right and left maxillary bones fuse together to form the upper jaw. The upper jaw is referred to as the maxilla

Which landmark is composed of fused spinous processes?

Median sacral crest

Which facial bones makeup the central portion of the bridge of the nose?

Nasal The 2 tombstone shaped nasal bones are found above the nasal cavity. They form a continuous bony bridge that connects the 2 sides of the face

Which of the following bones do not contain a sinus?

Nasal The sinuses found in the skull are collectively known as the paranasal sinuses because they encircle the nasal cavity. The nasal bones are small tombstone shaped bones that form the bridge of the nose and don't contain sinuses

Which of the following locations is not formed by part of the maxillae? Hint 1. The maxillary bone is known as the keystone bone of the face because it articulates with all facial bones except the mandible

Nasal septum The nasal septum is formed by the vomer and perpendicular plate of the ethmoid bone. The maxillary bone, although close in proximity, does not contribute to the structure of the nasal septum

Identify the articulation site that allows us to nod our head "yes" Hint 1. This articulation is found towards the top of the vertebra column

Occipital bone - atlas The padlike occipital condyles found on both sides of foramen magnum sit on top of the plate like superior articular processes of the atlas, forming the atlanto-occipital joint. The articular surfaces permit nodding of the head in a "yes" motion (flexion and extension)

Identify the area of the occipital bone that articulates with the vertebral column. Hint 1. This region makes up part of the atlanto-occipital joint

Occipital condyles The occipital condyles are found on the inferior surface of the skull on either side of foramen magnum. They articulate with the first cervical vertebra, the atlas. This articulation allows us to flex and extend the skull in a nodding "yes" motion.

Identify the region of the skull that articulates with the atlas. Hint 1. Recall the cranial bone that is in contact with the vertebral column.

Occipital condyles The occipital condyles found on both sides of foramen magnum sit on top of the atlas, forming the atlanto-occipital joint.

Which facial bones form the roof of the mouth?

Palatine bones Maxillary bones

Identify the posterior most region of the hard palate. Hint 1. The union of 4 bones forms the hard palate.

Palatine bones The horizontal plates of the palatine bones articulate with the palatine processes of the maxillary bones. The palatine bones form the posterior one-third of the hard palate.

Which part of the maxillary bones form the roof of the mouth? Hint 1. The maxillary together with another pair of bones form the roof of the mouth.

Palatine processes The palatine processes of the maxillary bones fuse on midline at the intermaxillary suture, forming the anterior portion of the hard palate (roof of the mouth).

Identify the part of the ethmoid bone that contributes to the nasal septum. Hint 1. Many projections of the ethmoid bone are not found on midline

Perpendicular plate The perpendicular plate is a plate like process that projects inferiorly on midline, forming the superior portion of the nasal septum.

Which part of the ethmoid bone forms part of the nasal septum?

Perpendicular plate The perpendicular plate of the ethmoid bone forms the superior portion of the nasal septum. The inferior portion of the nasal septum is formed by the vomer.

Identify the location of the occipital bone Hint 1. The occipital bone is a single (unpaired) bone.

Posterior surface and base of the cranium The occipital bone makes up the posterior part of the cranium.

Which region of the vertebral column is immediately inferior to the lumbar region? Hint 1. Recall the order of the 5 major regions that make up the vertebral column.

Sacral The sacrum is located below the lumbar region, articulating superiorly with L5 and inferiorly with the coccyx.

Identify the bony posterior wall of the pelvis Hint 1. Recall the part of the vertebral column that articulates with the coxal bones.h

Sacrum The sacrum articulates with the hip bones on the auricular surface of the ilium forming the sacroiliac joint. The sacrum makes up the back wall of the pelvic girdle.

The nasal septum occupies which anatomic plane? Hint 1. Which way does the nasal septum divide the nasal cavity: top from bottom, right from left, or front from back?

Sagittal The nasal septum lies in a midsagittal plane, dividing the nasal cavity into right and left halves

Identify the suture found between the 2 parietal bones.

Sagittal suture (The parietal bones meet at midline on the top of the skull, forming the sagittal suture which runs along the midsagittal plane.)

Identify the region of the sphenoid bone in contact with the pituitary gland. Hint 1. This region contains an area called the hypophyseal fossa.

Sella turcica The sella turcica is a central depression that houses the pituitary gland.

Which cranial bone spans the width of the cranial floor?

Spheroid (The sphenoid bone is the large bat shaped bone that spans the floor of the skull.)

Name the vertebral projection oriented in a median plane. Hint 1. There are 7 projections on this bone, only one of these is found on midline

Spinous process The spinous process extends posteriorly in a median plane. It serves as a site of muscle and ligament attachment

Identify the region of the temporal bone found superior to the external acoustic meatus that articulates with the parietal bone. Hint 1. The temporal bone makes up the lower lateral portion of the cranium.

Squamous part the squamous part helps form the squamous suture.

Identify the landmark on the temporal bone that is a pointy spine. Hint 1. There are many projections on the temporal bone,some are more blunt than spinous.

Styloid process The styloid process is a pointy, spinous projection that serves as a site of muscle attachment. It is easily broken off of human skull specimens.

Which region of the vertebral column is located superior to the thoracic region and which region is inferior to the thoracic region, respectively? Hint 1. The thoracic region occupies the chest area

Superiorly: cervical and inferiorly: lumbar The cervical region of the vertebral column is located above the thoracic region, and the lumbar region is found immediately below the thoracic region.

Which of the following thoracic vertebrae is the largest? Hint 1. Think about how the sizes of the individual vertebrae change from the top of the vertebral column to the bottom.

T12 There are 12 thoracic vertebrae. The size of the individual vertebrae increase from the top of the column to the bottom, therefore the last thoracic vertebra, T12, would be the largest.

The ethmoid bone is part of the axial skeleton

TRUE. The axial skeleton consists of the skull, vertebral column, and rib cage.

Identify the region on the zygomatic bone that forms part of the zygomatic arch. Hint 1. Recall a small projection on the zygomatic bone that forms a bony bridge with the temporal bone

Temporal process The temporal process of the zygomatic bone is a small bony projection that extends posteriorly to fuse with the zygomatic process of the temporal bone, forming the zygomatic arch.

Which region of the vertebral column is immediately superior to the lumbar region? Hint 1. Recall the order of the 5 major regions that make up the vertebral column.

Thoracic The 12 thoracic vertebrae are found above the 5 lumbar vertebrae in an articulated vertebral column

Identify a lateral projection of a vertebra. Hint 1. opened hint These projections serve as sites for muscle attachment.

Transverse process The transverse processes of a vertebra project laterally from the junction of the lamina and pedicle.

The lumbar vertebrae are found in the lower back. Hint 1. Recall the various regions of the vertebral column and their locations

True The 5 lumbar vertebrae are located between the thoracic region and the sacrum, making up the lower back.

The sphenoid bone contains a sinus. Hint 1. A sinus is a hollow cavity contained within the bone.

True The sphenoid bone contains the paired sphenoidal sinuses

The shape of the spinous process can be used to help determine if a vertebra is from the lumbar region Hint 1. Are the shapes of the spinous processes the same in the cervical, thoracic, and lumbar regions?

True The spinous process of a lumbar vertebra is blunt, not pointed as in the thoracic region or bifid as seen in the cervical region.

Identify the region of a rib that articulates with the transverse process of a vertebra. Hint 1. A projection on a rib contacts the transverse process of a vertebra

Tubercle The tubercle of a rib is located between the neck and shaft of the rib at the proximal end of the bone. It contacts the transverse process at the transverse costal facet.

Which bone forms the inferior portion of the nasal septum? Hint 1. Recall the 2 bones that form the nasal septum, and their relative positions to each other.

Vomer The vomer is a small facial bone that runs superiorly on midline to articulate with the perpendicular plate of the ethmoid, forming the inferior portion of the nasal septum.

What part of the sternum is palpated prior to giving CPR? Hint 1. The heart lies deep to this region

Xiphoid Process When administering CPR, care must be taken not to apply direct pressure to the xiphoid process. Injury can result from the xiphoid process being broken off and damaging vital organs found deep to it.

Identify the 2 bones that make up the zygomatic arch. Hint 1. The zygomatic arch makes up the prominence of the cheek.

Zygomatic bone and temporal bone The temporal process of the zygomatic bone and the zygomatic process of the temporal bone fuse to form the zygomatic arch

What is the anatomical name for the facial bones known as "cheekbones"?

Zygomatic bones The zygomatic bones are known as the cheekbones. Together, the zygomatic bone and the temporal bone form the zygomatic arch. This region is the bony foundation of the facial prominence known as the cheek.

Identify the region of the temporal bone that forms part of the zygomatic arch. Hint 1. The zygomatic arch forms a continuous bony bridge between the temporal and zygomatic bones.

Zygomatic process The zygomatic process is a projection of the temporal bone. It forms part of the zygomatic arch

Identify the region on the temporal bone that forms much of the zygomatic arch. Hint 1. Recall the name of the projection that forms a bony bridge with the zygomatic bone.

Zygomatic process The zygomatic process is the name of the elongated projection that extends out from the temporal bone reaching towards the zygomatic bone, forming most of the zygomatic arch.

The occipital bone forms part of the:

cranium The occipital bone is part of the cranium

Which of theses projections of the ethmoid bone are most visible in the nasal cavity?

middle nasal conchae The superior and middle nasal conchae protrude into the nasal cavity but the middle concha is most prominent

Identify the cranial nerve that passes through the olfactory foramina.

olfactory nerve (CN I) The olfactory nerves (CN I) pass through the olfactory foramina as they pass from the nasal cavity to the brain.