PNB 2264 Practical 1-Axial Skeleton/Muscles

components of compact bone

Osteon (contains central canal, canaliculi, osteocytes, lacunae, lamellae)

Perforating (Volkmann's) canals

Interstitial lamellae

Circumferential lamellae

components of spongy bone

trabeculae and red bone marrow

frontal bone (anterior view)

forms the forehead

zygomatic bones (anterior view)

form the cheekbones

maxillae bones

upper jaw

mandible

lower jaw

nasal bones

bridge of nose

ethmoid

an unpaired bone in the skull that separates the nasal cavity from the brain. It is located at the roof of the nose, between the two orbits.

cribriform plate of ethmoid bone

the part of the ethmoid that forms the roof of the nasal cavity

crista galli of ethmoid bone

superior projection in the middle of the cribriform plate of the ethmoid bone; providing a point of attachment for the dura mater, helping to secure the brain within the skull

temporal bones

form the sides and base of the cranium

mastoid process of temporal bone

sternocleidomastoid insertion

mandibular fossa of temporal bone

zygomatic process of temporal bone

external auditory meatus of temporal bone

The opening through which sound waves are conducted to the ear.

parietal bones (lateral view)

occipital bone

back of head

occipital condyles of occipital bone

rounded processes that articulate with the atlas (C1)

sphenoid bone

Bone that joins all of the bones of the cranium together

greater and lesser wings of sphenoid bone

greater wings are highlighted

lacrimal bones

make up part of the orbit at the inner angle of the eye

palatine bones

facial fused bones that form posterior part of hard palate

coronal suture

the suture between the parietal and frontal bones of the skull

saggital suture

joins the two parietal bones

lamboidal suture

joins both parietal bones with the occipital bone

squamous sutures

joins temporal and parietal bones

ear ossicles

malleus, incus, stapes

hyoid bone

the only bone that does not articulate with another bone

foramina

a passage or opening; a hole in a bone through which blood vessels or nerves pass

foramen magnum

means "big hole"

-the largest foramen and the entry for the spinal cord

jugular foramen

between temporal and occipital bones, entry of cranial nerves glossopharyngeal (IX), vagus (X), accessory (XI)

carotid canal (foramen)

anterior and medial to the jugular foramen, entry of internal carotid artery

superior orbital fissure (foramen)

between greater and lesser wings of the sphenoid bone; entry of cranial nerves

body of vertebrae

the thick, disc-shaped anterior portion which is the weight bearing portion

spinous process of vertebra

The portion of the vertebrae that sticks out posteriorly.

transverse process of vertebra

forms joint with ribs in thoracic region, site for muscle attachment in lumbar region

vertebral foramen

canal through which spinal cord passes

cervical vertebrae

C1-C7; neck

atlas (C1)

first vertebra, supports globe of head; body and no spinous process

axis (C2)

Odontoid process (dens) - provides a type of pivot and collar allowing the head and atlas to rotate around the dens

thoracic vertebrae

T1-T12; articulate with ribs; cartilaginous, symphysis joints

lumbar vertebrae

L1-L5; lower back

sacrum

5 fused bones

coccyx

3-5 fused bones; tailbone

sternum

consists of manubrium, body, xiphoid process

manubrium of sternum

top of sternum; articulates with ribs 1, 2, & clavicles

body of sternum

the middle portion of the sternum

xiphoid process of sternum

bottom of the sternum

ribs (24 total)

1-7 true ribs

8-10 false ribs

11-12 floating ribs

-costal cartilages

temporalis

closes jaw

O: temporal bone

I: mandible

masseter

closes jaw, elevates mandible

O: maxilla

I: mandible

digastricus

opens mouth, depresses mandible

O: mandible and mastoid process (temporal bone)

I: hyoid bone

sternocleidomastoid

flexes and laterally rotates the head

O: sternum and clavicle

I: mastoid process (temporal bone)

medial pterygoid

close jaw; lateral excursion (moving mandible laterally)

O: sphenoid bone

I: mandible

lateral pterygoid

lateral excursion; with medial pterygoid can lower mandible and allow yawning; opens jaw

O: sphenoid

I: condyloid process of mandible

trapezius

Elevates, depresses, retracts, and rotates the scapula;

O: C7-T12 and occipital bone

I: clavicle and scapula

latissimus dorsi

extends and adducts humerus; draws shoulder down and backwards

O:thoracic, lumbar, sacrum, and iliac crest

I: humerus

pectoralis major

flexion, adduction, and medial rotation of shoulder

O: sternum, clavicle, 1-6 ribs

I: humerus