Lesson 4 Flashcards
three main parts of the axial skeleton
- skull
- vertebral column
- bony thorax
the skull is composed of the… (2)
cranium and facial bones
two major areas of the cranium
cranial vault, and cranial floor
cranial vault
superior, lateral, and posterior walls of the skull
cranial floor
three concavities; anterior, middle, and posterior cranial fossae
coronal suture
connects the frontal bone to the parietal bone
lambdoid suture
connects parietal bone to the occipital bone
sagittal suture
connects the left and right parietal bones
squamous suture
connects parietal bone to the temporal bone
frontal bone: glabella
located between the orbital cavities
frontal bone: supraorbital foramen (notch)
opening above each orbit, passageway for blood vessels and nerves
parietal bone: sagittal suture
connects the two parietal bones
parietal bone: coronal suture
connects parietal bones to frontal bone
styloid process
muscle/ligament attachment site inferior to the external acoustic meatus
external acoustic meatus
the ear canal
zygomatic process
extension of bone into the upper buccal superior to the external acoustic meatus
mastoid process
muscle attachment site behind the styloid process and inferior to the external acoustic ear
petrous region: jugular foramen
passage for internal jugular vein, and cranial nerves IX (glossopharyngeal), X (vagus), and XI (accessory)
petrous region: carotid canal
passage for internal carotid artery
petrous region: internal acoustic meatus
passage for cranial nerves VII (facial), and VIII (vestibulocochlear)
occipital: foramen magnum
where the spinal cord enters the cranium to connect to the brain
occipital: occipital condyles
articulation site with first cervical vertebra (Atlas)
occipital: hypoglossal canal
passage for cranial nerve XII (hypoglossal)
sphenoid: greater wings
part of the orbital cavity; inferior to the lesser wing
sphenoid: sella turcica
midline of sphenoid bone
sphenoid: hypophyseal fossa
houses the pituitary gland; in the center of the skull superior to the foramen magnum (when looking from above)
sphenoid: lesser wings
anchors the dura mater (covering that encloses the brain)
sphenoid: optic canals
openings at the base of lesser wings for cranial nerve II (optic nerve)
ethmoid bone: crista galli
anchors dura mater (leathery connective tissue membrane that surrounds and protects the brain and spinal cord)
ethmoid bone: cribriform plate
allows olfactory fibers (cranial nerve I) from nasal mucosa to enter the brain
mandible
bottom portion of the jaw
mandible: body
bottom portion of the mandible; your chin
mandible: mandibular ramus
portion between the mandibular notch and the mandibular angle
mandible: mandibular angle
the rounded portion of the mandible connecting the body to the ramus
mandible: coronoid process
the second notch of the connection point of the mandible to the rest of the cranium
mandible: mandibular notch
the ‘swoop’ between the condylar process and coronoid process
mandible: condylar process
the connecting point of the mandible right next to your ear
maxilla: palatine process
anterior part of the hard palate
hard palate
created both by the maxilla and the palatine bone
vomer
the piece of bone behind the hard palate; in the center
zygomatic
cheek bone
lacrimal
a small bone deep to the maxilla, near the nasal bridge
nasal bone
the bone right in the center of the nose
what does the hyoid bone do?
serves as a point of attachment for many tongue and neck muscles
ethmoid bone
comprised of crista galli and cribriform plate
functions of sinuses (2)
- lighten the skull
- may act as resonance chambers for speech
sinusitis
inflammation of sinuses from bacterial infection or allergy
fontanelles
fetal skull contains areas of fibrous membranes
what do fontanelles do? (2)
- allow skull to compress slightly during birth
- allows for brain growth during late fetal life
by what age do the fontanelles completely ossify?
1.5-2 years old
craniosynostosis
birth defect that causes one or more of the sutures on a baby’s head to close earlier than usual
- cause is unknown, maybe genetic
