Skull

Neurocranium

braincase (grey) contains chondrocranium and dermatocranium

Visceral arches

The neurocranium is not derived from

Splanchnocranium

facial skeleton or vsicerocranium (purple)

Visceral arches

The splanchnocranium is derived from

Cranial base

floor of the cranial cavity, chondrocranium (purple)

Anterior fossa

Top

Middle fossa

Middle

Posterior fossa

Bottom

Paraxial mesoderm

gives rise to somites (top two arrows)

Somites

Paired blocks of mesoderm just lateral to the notochord of a vertebrate embryo. (Dermatome, myotome, sclerotome)

Mesenchyme

___ is of mesodermal origin in paraxial mesoderm

Neural crest

group of cells that develops from the embryo's ectoderm and contributes to the development of many vertebrate structures (bottom arrow)

Mesenchyme

___ is of neural plate origin (ectomesenchyme) in neural crest

endochondral ossification

Replacement of a cartilage model via bone

deposition after calcified cartilage is removed

Intramembranous ossifcation

Ossification directly within a membrane (no

cartilaginous phase)

Neurocranium

The ___ has both a cartilaginous and a membranous portion.

Cartilaginous neurocranium

Consists of hyaline cartilage developed from mesenchyme at the base of the developing skull (chondrocranium)

Sphenoid, ethmoid, temporal, and occipital bones

The chondrocranium includes parts of the

membranous neurocranium

Comprises the flat bones that form around the brain (dermatocranium)

Cranial vault bones

Membranous neurocranium includes the ___ except temporal squama

Cranial vault bones

frontal, parietal, temporal, occipital, sphenoid, ethmoid

Temporal squama

Membranous neurocranium Includes the cranial vault bones, with the exception of the

Viscerocranium

The facial bones also known as the ___ also has both a cartilaginous and a membranous portion

Paraxial mesoderm

The neurocranium is part of the

Neural crest cells

The viscerocranium is part of the

cartilaginous viscerocranium

comes from cartilage of the pharyngeal arches. This forms the ear bones and hyoid bone.

Meckels cartilage

1st arch: mandible precursor; degenerates to form the sphenomandibular ligament and the malleus and incus.

Reicherts cartilage

2nd arch: : forms the stapes, styloid process, and part of the hyoid.

Hyoid

3rd arch forms the

Laryngeal cartilage

4-6 arches form the

membranous viscerocranium

comes from mesenchyme of the first pharyngeal arch, undergoes intramembranous ossification and forms the facial bones.

Maxilla, zygomatic, temporal squama

The membranous viscerocranium is comprised of

Synarthroses

Partially movable joints

Synchondrosis

Only occur between bones derived from

All form in the cranial base. (Synarthroses)

Sutures

Occur between cranial bone of either membranous or

cartilaginous origin.

(Synarthroses)

Diarthroses

freely movable joints

Frontal

Black

Ethmoid

Blue

Sphenoid

Red

Occipital

Yellow

Presphenoidal synchondrosis

Green

Sphenooccipital synchondrosis

Purple

Interoccipita synchondrosis

Pink

temporomandibular joint

The joint formed where the mandible and cranium meet, just in front of the ear. (Diarthrodial)

Compact bone

Hard, dense bone tissue that is beneath the outer membrane of a bone

trabeculated bone

Spongy bone that contains hemopoietic tissue

Frontal sinus

Black

Maxillary sinus

Green

Ethmoidal sinus

Blue

Ethmoidal sinus

Blue

Temporal air cell

Yellow

Sphenoidal sinus

Red

Sphenoidal sinus

Bottom

Frontal sinus

Top

Maxillary sinus

2nd bottom

Ethmoidal sinus

2nd top

Arteriovenuous impressions

Venous sinus impressions

Musculotendinous/lingamentous attachments