L2: Embryology of head and neck

Question 1

when does head formation take place ?

Answer 1

3-4 weeks IUL

Question 2

what seperates the stomadeum from the foregut ?

Answer 2

buccopharengeal membrane

Question 3

what develops from the floor of the stomedum ?

Answer 3

heart

Question 4

when does the buccopharyngeal membrane rupture?

Answer 4

on day 28

Question 5

what develops from the roof of the buccopharengeal membrane .?

Answer 5

rathe’s pouche

Question 6

what does rathe’s pouch give rise too?

Answer 6

anterior pituitary

Question 7

when do the pharengeal arches begin to develop?

Answer 7

early in 4th week due to mesodermal proliferation

Question 8

how many pharyngeal arches are there?

Answer 8

4 defined pairs and 2 rudimentary pairs

Question 9

when does formation of pharengeal arches end?

Answer 9

end of 4th week

Question 10

what are pharyngeal arches separated by from the outside ?

Answer 10

clefts

Question 11

what are the pharyngeal arches separated by from the inside ?

Answer 11

pouches

Question 12

what does each pouch give rise too ?

Answer 12

1st pouch: tympanic cavity . mastoid antrum , auditory tube
2nd pouch: palatine tonsil
3.)inferior parathyroid gland + thymus
4th pouch : superior parathyroid and parafollicular cells of thyroid

Question 13

when does the development of the face occur?

Answer 13

4-8weeks IUL

Question 14

when do nasal placodes appear?

Answer 14

by the end of the 4th week

Question 15

what separates nasal prominence from maxillary swelling?

Answer 15

nasolacrimal groove

Question 16

when does development of the palate happen?

Answer 16

5th - 12th week

Question 17

what forms the upper lip?

Answer 17

fusing of medial nasal swelling and maxillary swelling

Question 18

what forms filtrum of lip?

Answer 18

medial nasal swelling

Question 19

what froms the ala of the nose?

Answer 19

lateral nasal swelling

Question 20

what forms the primary palate ?

Answer 20

medial nasal swelling merging with eachother

Question 21

what is the buccopharengeal membrane composed of ?

Answer 21

ectoderm and endoderm ( no mesoderm)

Question 22

where will the pharyngeal arches begin development ?

Answer 22

lateral side of pharynx

Question 23

list the names of the first 4 pairs of pharengeal arches and what their nereve supply is :

Answer 23

1.) mandibular arch : trigeminal \
2.)facial arch : facial nerve
3.) glossopharengeal arch : glossopharengeal nerve
4.)vagus arch : vagus nerve

Question 24

when do ectodermal thickenings ( nasal placodes ) show up in the frontonasal swelling ?

Answer 24

end of 4th week / beggining of 5th week

Question 25

what causes cleft upper lip?

Answer 25

Due to failure of fusion between maxillary process and Medial nasal process