Lect. 23 - Skeletal system Development II Flashcards Preview

Embryo Exam II > Lect. 23 - Skeletal system Development II > Flashcards

Flashcards in Lect. 23 - Skeletal system Development II Deck (11):
1

Viscerocranium

(Refers to pharyngeal arches); surrounds oral cavity and pharynx; cartilagenous portion - forms pharyngeal arch I and II; membranous portion forms - temporal, zygomatic, maxillary, nasal, lacrimal, alanine, vomer, pterygoid plates, mandible, tympanic ring

2

Components of the pharyngeal arches

Pharyngeal arch I: mechel's cartilage, malleus, incus
Pharyngeal Arch II: Reichert's cartilage, stapes, styloid

3

What is the origin of the mesenchyme that forms the Viscerocranium?

Mostly from neural crest

4

4 components of each pharyngeal arch?

Skeletal element, muscles, branch of specific cranial nerve, artery

5

Basiooccipital portion of chondrocranium is derived from?

Parachordal cartilages and occipital sclerotomes

6

What is the cause of the elongation of primary ossification centers?

Shh

7

Fontanelle

Intersection of more than 2 bones

8

Fusion of suture pathway

Noggin is expressed in all sutures; FGF-2 blocks Noggin; Noggin blocks BMP which leads to closure of sutures

9

What results in the neurocranium arising?

Inductive interactions of surrounding mesenchyme - characterized by transient appearance of type II collagen and cartilage-specific proteoglycan

10

Neurocranium

Part of the skull that surrounds the brain; has cartilaginous portion and membranous portion; base formed from chondrocranium - origin of occipital, sphenoid, ethmoid, and parts of temporal; membranous part - origin of occipital, parietal so, frontals, part of temporals

11

Membranous portion of the viscerocranium forms what?

Part of temporal, zygomatic, maxillary, nasal, lacrimal, alanine, vomer, pterygoid plates, mandible, tympanic ring