Part B: The Bones of the Skull

frontal (marking and function)

marking → supraorbital foramen

description→ forehead, anaterior part of cranial base, roofs of orbits (eye sockets)

function → protects brain, eyes, and nasal passages

ethmoid

markings → crista galli, cribiform plate, perpendicular plate, olfactory plate

description→ medial wall of orbits, anterior part of cranial base

function → supporting structurestructure of nasal cavity and forms surface area inside it

occipital

markings → occipital condyle, foramen magnum

description → posterior part of cranial cavity base

function → protects cerebellum and occipital lobes

sphenoid

markings → optic foramen

description → wedge-shaped “butterfly”; lies at middle part of cranial base

function → “keystone” holds all cranial base bones together

parietal

description → 2 bones form sides and roof of cranial cavity

functions → protrusions and depressions accommodate blood vessels and superficial CT covering the brain

temporal

markings → mandilar fossa, styloid process, mastoid process, external auditory meatus

description → inferior lateral aspects of cranial cavity base

function → protects temporal lobe and cranial nerves

mandible

markings → condylar process

description → lower jawbone, largest, strongest

function → open and closing mouth; chewing, speech

maxilla

markings → infraorbital foramen, palatine process

description → paired jawbones form upper jawbone; articulate w/ every favial bone except mandible; most of the hard palate

function → hold upper teeth, forms orbit, nose and palate; communication and mastication

zygomatic

desc. → cheekbones

function → shape n structure

palatine

desc → posterior portion of hard palate

function → roof of mouth, lateral walls of nose, orbital floors

vomer

desc → triangular bone that forms inferior part of nasal septum

function → support nassal septum and divide nasal cavity in 2

inferior nasal concha

desc → inferior to middle nasl conchae of ethmoid; project into nasal cavity

function → increase surface area of nasal cavity and help swirl and filter air before it passes into the lungs

nasal

desc → small, flattened, rectangular bones that form bridge of nose

function → protect upper entry to the nasal cavity and provide attachment for thin muscles of facial expression

lacrimal

desc → fingernail size and shape, smallest, psoterior and lateral to nasal bones forming a medial wall of each orbit

function → contains lacrimal fossa (a tunnel in maxilla) that houses the lacrimal sac that gathers tears

list the bones that make up the bony wall of the orbits

1. frontal

2. zygomatic

3. maxilla

4. ethmoid bone

5. lacrimal bones

6. sphenoid bones

7. palatine bones

list the cranial n facial bones that are unpaired

cranial (4):

1. frontal

2. occipital

3. sphenoid

4. ethmoid

facial (2):

1. vomer

2. mandible

name the bones that make up the hard palate

1. palatine process of the maxila (anterior)

2. horizontal plate of the palatine bone (posterior)

list the bones that form the nasal septum

1. vomer

2. perpendicular plate of ethmoid bone

what bones form the zygomatic arch?

1. zygomatic bone

2. temporal bone