Anatomy Lec 9 - Embryo

Front 1

what is hypo & hypertelorism cyclopia?

Back 1

- space between eyes are too close or too far apart

Front 2

what arch is treacher collins & pierre robin associated with?

Back 2

- arch 1

Front 3

how does the neural crest form?

Back 3

- via delamination of the neuroectoderm at lateral margins of neural plate

Front 4

which level of the neural crest is affected in DiGeorge?

Back 4

- problem is with vagal (post-otic) neural crest cells

- get problems of immune system, great vessels

Front 5

what happens to paraxial mesoderm rostral to the otic vesicle?

Back 5

- paraxial mesoderm does not form epithelial somites

- forms individual unit called somitomere

Front 6

what comes from the somitomeres?

Back 6

- muscles that will be innervated by the cranial nerves

Front 7

what are the placodes?

Back 7

- epithelial thickenings that give rise to neurons & other parts of nervous system

Front 8

does the placode give rise to the proximal or distal part of the ganglion?

Back 8

- distal

Front 9

what are the 3 origins of bone for skull & face?

Back 9

- dermal bone origins - contributed by condenstation of mesenchymal tissue originates from neural crest

- cartilage precursor

- green are pharyngeal arch cartilage

Front 10

pharyngeal arch 1: artery? muscles? nerve?

Back 10

- artery: terminal branch of maxillary

- muscles: muscles of mastication, everything by V & tensors

- CN: V2 & V3

Front 11

pharyngeal arch 2: artery? muscles? nerve?

Back 11

- artery: stapedial artery, corticotympanic

- muscles: facial expression & stylohyoid & post. belly digastric & stapedius

- CN: facial CNVII

Front 12

pharyngeal arch 3: artery? muscles? nerve?

Back 12

- artery: common carotid

- muscles: stylopharyngeus

- nerve: IX

Front 13

pharyngeal arch 4: artery? muscles? nerve?

Back 13

- artery: arch of aorta, right subclavian

- muscles: pharynx

- nerve: superior laryngeal branch of X

Front 14

pharyngeal arch 6: artery? muscles? nerve?

Back 14

- artery: ductus arteriosus

- muscles: intrinsic muscles of larynx

- nerve: recurrent branch of X

Front 15

which cartilages come from 1? from 2? 3? 4?

Back 15

- 1: palatopterygoquadrate (contributes to wing of sphenoid), meckel's (gives rise to malleus & incus)

- 2: relchert's cartilage (contributes to stapes & lesser horn of body of hyoid)

- 3: most of hyoid bone

- 4: thyroid & cricoid cartilage

Front 16

what are the 5 swellings of the face?

Back 16

- frontonasal process (corresponds to opthalmic division of V1)

- paired maxillary processes

- paired mandibular processes

Front 17

what are the two parts of the frontonasal process? how does this happen? how do these form the nose?

Back 17

- medial & lateral formed by invagination of the olfactory placode

- medial process fuses to form intermaxillary process gives rise to philtrum - middle of nose/lips)

Front 18

what is the primary palate an extension of? what is the other part of the palate?

Back 18

- intermaxillary process

- as two maxillary processes grow they give rise to the palatine shelves that grow together to form rest of hard palate --> tongue needs to be out of way

Front 19

what does the 1st pharyngeal cleft become?

Back 19

- becomes the external auditory meatus

Front 20

what is the endoderm for pharyngeal arch 1? 2? 3? 4?

Back 20

- 1: median tongue bud & lateral lingual swellings - becomes ant 2/3 of tongue

- 2: copula

- 3: mucosa of posterior 1/3 of tongue

- 4: dorsal region of tongue

Front 21

which pharyngeal pouches give rise to the parathyroid?

Back 21

- 3 (inferior), 4 (superior)

Front 22

what does the thyroglossal duct connect?

Back 22

- connects the thyroid & the tongue --> moving down via foramen cecum

Front 23

which pharyngeal pouch gives rise to the thymus? what happens in thymic aplasia?

Back 23

- 3

- in thymic aplasia the 3rd pouch does not descend nor does the parathyroid associated with that pouch (inferior parathyroid)

Front 24

who gives rise the branchial body & what does it do?

Back 24

- 6th pharyngeal pouch

- it is buried within the thyroid, gives rise to C cells within PT gland --> secrete calcitonin

Front 25

what happens in digeorge syndrome?

Back 25

- problems with vagal (post otic) neural crest cells & 3rd & 4th pharyngeal pouches --> end up with thymic hypoplasia, hypocalcemia b/c parathyroid not ok, but branchial body (doing C cells are ok - from 6 pouch)

Front 26

which part of the eye is derivative of CNS & which part is neural crest?

Back 26

- retina is derivative of CNS

- surrounding parts are neural crest - sclera, choroids, cornea

Front 27

what happens in eve development?

Back 27

- evagination of optic vesicle - forms the optic cup (forms retina, ciliary body & iris)

- lens placode invaginates & gives rise to crystalin - clarity of lens in adult

Front 28

what is holoprosencephaly?

Back 28

- not two cerebral hemispheres - connection between them is the corpus callosum

Front 29

what is the prechordal plate?

Back 29

- major organizing center

- protein secreted is SHH