Z15 - Development Of The Pharynx

Front 1

the cranial part of the foregut, (the pharyngeal gut), develops into ____ and ____ structures.

Back 1

head and neck

Front 2

the pharyngeal gut (cranial part of the foregut) is made up of what 3 layers?

Back 2

-the endodermal tube- internally
-medoderm and nnc that develop into mesenchyme
-ectoderm- externally

Front 3

during which weeks are the pharyngeal arches, pharyngeal clefts, and pharyngeal pouches formed?

Back 3

4th week

Front 4

the __________ ____ are 6 pairs of swellings

Back 4

the pharyngeal arches

-the 5th degenerates

Front 5

the _________ ____ are external surface grooves between the pharyngeal arches

Back 5

the pharyngeal clefts

Front 6

mesenchyme is formed from _______ and ___

Back 6

mesoderm and NCC's

Front 7

mesoderm vs NCC become what, eventally in the head and neck area

Back 7

mesoderm- ob. m. in vascular tissues
NNC- bones of face, part of thymus, thyroid...

Front 8

within each pharyngeal arch is are the following: an artery, nerve, cartilage, and muscle.

what do these become?

Back 8

artery- aortic arch
nerve- cranial nerve
cartilage- bones and ligaments (from NCC's)
muscle- muscular components (from mesoderm) migrate adn carry cranial n. with them

Front 9

what skeletal structure, muscular structures and nerves come from the 1st pharyngeal arch?

Back 9

sk: mandibular (meckle's) cartilage: Malleus and Incus
mm: mm of mastecation, mylohyoid, ant. belly of digastric, tensor tympani, tensor veli palatini mm
nn: mandibular division of trigeminal nerve (V3)

Front 10

the _______ ____ ate between the pharyngeal arches within the pharyngeal gut (internally) (endoderm)

Back 10

pharyngeal pouches

Front 11

T/F -The mandible does NOT come from the 1st pharyngeal arch.

Back 11

True!!!

Front 12

what skeletal structure, muscular structures and nerves come from the 2nd pharyngeal arch?

Back 12

sk: Reichart's Cartilage: stapes, styloid process of temporal bone, lesser horn of hyoid bone, superior body of hyoid bone, stylohyoid lig.
mm: mm of facial expresssion, stapedius, stylohyoid, posterior belly of digastic mm
n: Facial n. (VII)

Front 13

what skeletal structure, muscular structures and nerves come from the 3rd pharyngeal arch?

Back 13

sk. struct: greater horn of the hyoid bone, inferior body of hyoid bone
m: stylopharyngeus m.
n: glossopharyngeal n. (IX)

Front 14

what skeletal structure, muscular structures and nerves come from the 4th pharyngeal arch?

Back 14

sk. st.: laryngeal cartilages
mm: pharyngeal constrictors mm, levator veli palatini m., cricothyroid m
n: vagus (X)--> superior laryngeal n.

Front 15

what skeletal structure, muscular structures and nerves come from the 5th pharyngeal arch?

Back 15

NOTHING... it degenerates

Front 16

what skeletal structure, muscular structures and nerves come from the 6th pharyngeal arch?

Back 16

sk. st.: laryngeal cartilages
mm: intrinsic mm of larynx
n. vagus (X) --> recurrent laryngeal nn.

Front 17

the vocal folds form between which 2 pharyngeal arches?

Back 17

4 & 6 (superior and inferior thyroid cartilages)

Front 18

there are ___ pairs of pharyngeal arches, ___ pairs of pharyngeal clefts, and ____ pairs of pharyngeal pouches

Back 18

6 arches, 4 clefts, and 4 pouches

Front 19

which cleft deepens to give rise to the external acoustic meatus?

Back 19

1st pharyngeal cleft

Front 20

the 2nd pharyngeal cleft outgrows the 3rd and 4th arches to enclose the 2nd, 3rd, anf 4th clefts into a temporarily formed cavity called the ________ _______

Back 20

cervical sinus

Front 21

what do each of the 4 pharyngeal pouches form?

Back 21

1st- laterally = tympanic cavity & medially = auditory tube
2nd- palatine tonsil
3rd- dorsal = inferior parathyroid gland
ventral = thymus
4th- dorsal = superior parathyroid glans
ventral = ultimobranchial body (associated with the parafollicular cells of the thyroid)

Front 22

what is the ultimobranchial bodies significance as it forms from the 4th pharyngeal pouch?

Back 22

it migrates caudally to incorporate into the thyroid gland and its parafollicular cells that are dispersed throughout and secrete calcitonin

Front 23

the anterior 2/3 of the tongue forms from which phar. arch?

Back 23

1st

Front 24

the posterior 1/3 of the tongue forms from which phar. arch?

Back 24

3rd

Front 25

the extreme posterior tongue and epiglottis are formed by which phar. arch?

Back 25

4th

Front 26

the 2nd phar arch forms which part of the tongue?

Back 26

NONE!!

Front 27

the anterior 2/3 of the tongue are formed from __ distal tongue bud(s) and ___ medial tongue bud(s); which outgrow which?

Back 27

2 distal tongue buds (lateral lingual swellings)
1 medial tongue bud (tuberculum impar)

distals outgrow medial and fuse

Front 28

the _____ _____ forms at the most posterior part of the tuberculum impar of the 1st arch

Back 28

foramen cecum

Front 29

general sensory for the anterior 2/3 of tongue is done by ________, and taste sensation is done by ___________.

Back 29

general sensory: Lingual n. (V3)
taste: chorda tympani

Front 30

the posterior 1/3 of the tongue has general sensation from the ______________ and taste sensation from ___________

Back 30

glossopharyngeal n. (IX) does both general sensory and taste sensation for posterior 1/3 of tongue

Front 31

the extreme posterior portion of tongue and epiglottis have general sensory innervations by _______

Back 31

vagus n. (X)

Front 32

the ________ gland is derived form a median endodermal thickening on teh floor of the pharynx

Back 32

thyroid; it migrates caudally and maintains connection with pharynx via the thyroglossal duct

Front 33

the 2 lobes of the thyroid are separated by an ______ and sometimes there is a 3rd ________ lobe

Back 33

isthmus

pyramidal lobe

Front 34

what is the final position of the thyroid in reference to the trachea and remnants?

Back 34

the thyroid ends up anterior to the trachea, the thyroglossal duct, in theory, degenerates, and the foramen cecum in the tongue is a remnant of the thyroid's descent.

Front 35

CC: Branchial cyst
-abnormality
-embryological explanation
-clinical
-treatment

Back 35

-abnormality: spherical cyst along the anterior border of the SCM m.
-emb: cervical sinus fails to obliterate
-clinical: increase in size due to fluid and cellular debris
-treatment: surgical removal

Front 36

CC: Branchial fistula
-ab
-emb
-clinical
-treat

Back 36

-ab: open tract from the pharynx to the lateral surface of the neck
-emb: persistence of the 2nd pharyngeal cleft & the 2nd pharyngeal pouch that merge during development
-clinical: discharge of fluid from the neck and infection
-treat: surgically remove

Front 37

CC: Thyroglossal duct cyst
-ab
-emb
-clinical
-treat

Back 37

ab: cyst forming anywhere along thyroglossal duct
-emb: thyroglossal duct fails to degenerate
-clinical: swelling long midline of neck and infection
-treat: surgical removal of the cyst and other remnants of the duct

Front 38

CC: First arch syndrome
-emb
-2 manifestations

Back 38

-emb: insufficient migration of ncc
1) Treacher-Collins syndrome
2) Pierre-Robin syndrome

Front 39

CC: Treacher-Collins syndrome

cause

Back 39

a first arch syndrome

-NCC fail to migrate into first arch completely; malformed ears

Front 40

CC: Pierre-Robin syndrome

clinical

Back 40

a first arch syndrome

-underdevelopment of mandible
-cleft palate
-glossoptosis (posterior placement of the tongue)

Front 41

CC: DiGeorge Syndrome
ab:
emb:
clinical:

Back 41

ab: thymic aplasia/absence of parathyroid glands
emb: failure of 3rd and 4th pharyngeal pouches to differencitate into thymus and parathyroid gland
clinically: immunologic problems, hypocalecemia, microgathia (small jaw), cardiovascular defects (persistent truncus arteriosis- atrial septum normally needs ncc to separate into aorta and pulmonary a.)