Facial Development

Question 1

Which bones of the inner ear are derived from Meckels cartilage

Answer 1

brachial arch cartilage #1: maleus and incus

Question 2

What bone of the inner ear is derived from Reicharts cartilage

Answer 2

brachial arch cartilge #2: stapes

Question 3

A bifid uvula results from failure to complete fusion of the _____?

Answer 3

palatine shelves

Question 4

Abnormal closure of the neural tube can result from a lack out ______ in a mothers diet

Answer 4

folic acid

Question 5

Melanocytes are derived from cells of what embryonic structure?

Answer 5

neural crest cells

Question 6

The trilaminar embryonic disc is comprised of which cell layers

Answer 6

Ectoderm, mesoderm, endoderm

Question 7

“Extrusion of the meningeal layers through the fetal cranium” is an accurate description of which neural tube defect

Answer 7

Meningocele

Question 8

During what period of development do the germ layers mature and differentiate into specific tissues and organ systems

Answer 8

embryonic

Question 9

Which cranial nerve supplies innervation to the tissues of the 4th pharyngeal arch

Answer 9

vagus (X)

Question 10

Which 2 pharyngeal arches contribute to the formation of the hyoid bone

Answer 10

2nd and 3rd arch

Question 11

List the tissues of neural crest origin

Answer 11

(FATDMC): Dorsal root ganglion, melanocytes, adrenal medulla, facial bones, cartilage, and all tooth and periodontal structures EXCEPT enamel and gingiva

Question 12

List the tooth/periodontal cells derived from neural crest cells

Answer 12

(DAPPC): dentin, pulp, periodontal ligament, cementum, alveolar bone

Question 13

In lecture, what was the definition of cyst

Answer 13

cavity lined by cells (either empty or fluid-filled)

Question 14

The palatine shelves complete fusion during the _____ and ____ week

Answer 14

begins: 8th week of gestation
completes: 12th week

Question 15

The thyroid gland invaginates at the _______

Answer 15

foramen cecum (brachial arch 1)

Question 16

Which one of the cranial nerves gives sensory (taste) function in the anterior 2/3 of the tongue

Answer 16

Facial nerve (CN VII) –> via chorda tympani branch

Question 17

the parathyroid glands are derived from the ectoderm, lining which pharyngeal pouches?

Answer 17

3rd brachial pouch–> inferior parathyroid
4th brachial pouch–> superior parathyroid

Question 18

If cells that give rise to the thyroid gland fail to migrate from their site of origin, at which of the following anatomical sites would you LEAST likely find the ectopic thyroid?

Answer 18

neck

Question 19

The embryonic mesoderm cell layer is derived from the _______ layer.

Answer 19

Ectoderm (epiblast)

Question 20

Implantation of the embryoblast into the uterine wall begins at day ____ following conception, and is completed by day ____ .

Answer 20

Day 4, Day 10

Question 21

What structures are the precursors of the vertebral column, ribs, associated back muscles
and overlying dermis?

Answer 21

somites (formation induced by notocord)

Question 22

Cleft lip results when there is a lack of fusion between the ________ and _________ processes

Answer 22

a. Median nasal process
b. Maxillary process

Question 23

The posterior 1/3 of the tongue is derived from the _______ of the ______ pharyngeal
arch.

Answer 23

a. Hypobranchial eminence
b. 3rd pharyngeal arch

Question 24

According to the textbook (Berkovitz, et al), the hard palate ossifies intramembranously from ___ centers of ossification.

Answer 24

4 (secondary)

Question 25

The anterior 2/3 of the tongue is derived from what pharyngeal arch/intermediate
structure combination?

Answer 25

1st pharyngeal arch
lateral lingual swellings

Question 26

At 3 months of fetal development, the head length relative to total trunk (i.e., thorax and abdomen) length is approximately ___%.

Answer 26

50%

Question 27

Cranial nerve ___ is responsible for sensory innervation to the posterior 1/3 of the
tongue.

Answer 27

Glossopharyngeal (CN IX)

Question 28

What percentage of all cases of orofacial clefts are isolated cleft lips?

Answer 28

25%

Question 29

Which cranial nerves innervate the tongue?

Answer 29

V, VII, IX, X, XII