Reading Week 1

Question 1

What forms the frontonasal process?

Answer 1

the mesenchyme of the developing forebrain

Question 2

What type of tissue gives rise to the nasal and oral placodes?

Answer 2

local thickening of ectoderm

Question 3

When do the two mandibular processes fuse in the midline to form the lower jaw ?

Answer 3

in the 6 week old embryo

Question 4

What is the fully developed lip innervated by?

Answer 4

only the maxillary division of the trigeminal nerve

Question 5

What forms the facial muscles?

Answer 5

derived from mesenchyme of the second pharyngeal arches

Question 6

What are the facial muscles, primitive lips and cheeks innervated by?

Answer 6

the facial nerve

Question 7

What is the mesenchyme of the frontonasal process formed from?

Answer 7

cranial neural crest cells

Question 8

What is the mesenchyme of the maxillary and mandibular processes derived from?

Answer 8

cranial neural crest cells and mesoderm

Question 9

What are the four fundamental mechanisms that underlie all embryonic development?

Answer 9

growth, morphogenesis, cel differentiation, and pattern formation

Question 10

What turns on sonic hedgehog signaling (Shh)?

Answer 10

retinoic acid

Question 11

What is Shh involved in?

Answer 11

regulation of craniofacial development

Question 12

What do the nasal placodes form?

Answer 12

the olfactory epithelium

Question 13

What do the lens placodes form?

Answer 13

eventually become the lens of the eyes

Question 14

What do the otic placodes form?

Answer 14

first part of the ears to form and will eventually become the inner ear

Question 15

What is holoproscencephaly?

Answer 15

congenital abnormality where the developing forebrain fails to divide into separate hemispheres and ventricles

Question 16

What is macrostomia?

Answer 16

enlarged oral orifice

Question 17

What is microstomia?

Answer 17

small oral orifice

Question 18

What is astomia?

Answer 18

lack of oral orifice

Question 19

What forms facial clefts ?

Answer 19

failure of fusion of maxillary and medial nasal processes
-can be unilateral or bilateral

Question 20

What is formed by the first pharyngeal arch?

Answer 20

the maxillary and mandibular processes

Question 21

What causes first arch syndromes?

Answer 21

insufficient migration of neural crest cells and decreased cell proliferation

Question 22

when does the secondary palate form?

Answer 22

between the 6th and 8th week of development

Question 23

What happens in the oral cavity during the 7th week of development?

Answer 23

the tongue fills up a majority of the oral cavity

Question 24

When does the stomodeum enlarges and the tongue drop?

Answer 24

during the 8th week

Question 25

After the palate fuses, what happens?

Answer 25

it must from the vertical and horizontal position

Question 26

What is a necessary enzyme for palate formation?

Answer 26

hyaluronan

Question 27

After the palate is formed, what replaces the hyaluronan?

Answer 27

proteoglycans

Question 28

What helps to hold the palate shelves together?

Answer 28

sticky glycoproteins

Question 29

What type of cell cell junction is seen between the palate shelves?

Answer 29

desmosomes

Question 30

Where is the maxillary ossification center?

Answer 30

above the developing deciduous canine tooth germ

Question 31

What are palatal cysts?

Answer 31

remnants of the nasopalatine ducts -anterior midline of the palate

Question 32

What are palatal clefts?

Answer 32

clefts in the palate that form due to any disturbance of any process during palatogenesis

Question 33

Are clefts due to unifactorial distrubances?

Answer 33

no, typically there are many factors that are present -genetics -environment -rubella -viruses -excess vitamins

Question 34

What cartilage comes from the first pharyngeal arch and forms the initial outline of the mandible?

Answer 34

merkel's cartilage

Question 35

Where is the ossification center of the mandible?

Answer 35

near the future mental foramen

Question 36

What else is formed from Merkel's cartilage?

Answer 36

ear ossicles

Question 37

When does the symphysis of the mandible finally fuse?

Answer 37

year 2

Question 38

How does the maxilla grow?

Answer 38

by bone remodeling

Question 39

How many buds does the anterior 2/3 of the tongue form from?

Answer 39

3 -two distal -1 median

Question 40

How many swellings is the posterior tongue formed from?

Answer 40

one -hypopharyngeal eminence

Question 41

What influences he development of the tongue muscularture?

Answer 41

Smad4-mediated transforming growth factor beta

Question 42

What helps to form filiform papillae?

Answer 42

BMPs

Question 43

What signals work with funigform papillae formation?

Answer 43

Shh, Wnt6, Lef1, Sox2, and EGF

Question 44

What is required for taste bud development?

Answer 44

Sox2

Question 45

Where does the thyroid gland develop?

Answer 45

between the median tongue bud and the copula

Question 46

What is the first endocrine gland to develop?

Answer 46

the thyroid gland

Question 47

What are the muscles of the tongue innervated by?

Answer 47

hypoglossal nerve

Question 48

What is the first salivary gland formed?

Answer 48

parotid gland

Question 49

What is the second salivary gland formed?

Answer 49

submandibular gland

Question 50

What is ankyloglossia?

Answer 50

tongue tie

Question 51

What is microglossia?

Answer 51

small tongue

Question 52

What is macroglossia?

Answer 52

large tongue

Question 53

What is fissured tongue?

Answer 53

tongue with large groups

Question 54

What is bifid tongue?

Answer 54

tip of the tongue may be split

Question 55

What is medium rhomboid glottis?

Answer 55

nonpapillated, reddish region in the anterior 2/3s of the tongue

Question 56

What is a lingual thyroid?

Answer 56

the thyroid is retained in the foramen cecum at the back of the tongue