Block 1 week 2 skull embry

Question 1

difference between neurocranium and viscerocranium

Answer 1

Neurocranium = forms around the rostral end of the neural tube (brain case)

Vescerocranium forms around the rostral end of the gut tube (face)

Question 2

what kind of ossification is used in making each bone of the skull?

Answer 2

cranial vault (parietal, frontal, squamous occipital) - membranous

Everything else - cartilaginous

Question 3

What embryological cells form the bones of the face and frontal skull?

What type of ossification do they go through?

Answer 3

Neural crest cells

Endochondral

Question 4

What embryological cells form the mesenchyme/cartilages to the base of the skull?

What type of ossification do they go through?

Answer 4

occipital somites

Cartilaginous (endochondral)

Question 5

Paraxial mesoderm (somites and somitomeres) forms what bones in the skull?

Answer 5

Parietal, occipital, petrous temporal

Question 6

neuroectoderm forms which bones of the skull?

proecess?

Answer 6

Viscerocranium. (frontal bone, Sq temporal, sphenoid, and all of the bones of the face.)

Neuroectoderm -> neural cres cells -> Migrate into the pharengeal arches where they form mesenchyme -> form bones

Question 7

craniosynostosis

Answer 7

premature closure of one or more sutures that produces a misshapen skull.

Question 8

Brachycephaly

Answer 8

fusion of coronal suture produces a shortened front-to-back diameter of skull (“flat-head”).

Question 9

Oxycephaly, turricephaly or acrocephaly

Answer 9

fusion of coronal & lambdoidal sutures produces a “tower skull”.

Question 10

Plagiocephaly

Answer 10

fusion of coronal & lambdoidal sutures unilaterally produces an asymmetrical skull

Question 11

Scaphocephaly

Answer 11

fusion of the sagittal suture produces a long front-to-back diameter skull.

Question 12

Cranioschisis

Answer 12

skull version of spina bifida.

is a skull defect the through which the meninges and/or brain herniate. (NTD)

Question 13

Meningohydroencephalocele:

Answer 13

Herniation of meninges, brain & ventricle in craniochisis.

Question 14

Apert Syndrome, what is it.

Mutation in what?

Answer 14

Autosomal dominant
craniosynostosis
syndactyly of hands and feet
mental retardation.

Mutation in fibroblast growth factor receptor 1 and 2

Question 15

Parietal bone, occipital bone, petrous temporal bones come from what type of embryological cells?

Process?

Answer 15

Intrtaembryonic mesoderm -> Paraxial mesoderm ->somites -> sclerotome -> base of skull

Question 16

Frontal bone, sphenoid bone, squamous temporal bone, and facial bones come from what embryological cells?

Answer 16

Neuroectoderm -> neural crest -> migrate to pharengeal arches to form mesenchyme -> bones of face and skull

Question 17

Name for the anterior fontanelle?

Answer 17

bregma

Question 18

Meningoencephalocele:

Answer 18

Herniation of the meninges plus the brain (type of cranioschisis)