EMBRYOLOGY

Question 1

which one of the 6 pharyngeal arches is rudimentary (not in humans)

Answer 1

5

Question 2

what are the 3 components of each pharyngeal arch

Answer 2

artery
nerve
cartilage (muscles and bones that arise correlate to the nerve and blood supply)

Question 3

which pharyngeal arch does CN IX come from

Answer 3

pharyngeal arch 3

Question 4

which pharyngeal arch does CN VII come from

Answer 4

pharyngeal arch 2

Question 5

which pharyngeal arch does CN V2 and CN V3 come from

Answer 5

pharyngeal arch 1

Question 6

which pharyngeal arch does the superior branch of CN X come from

Answer 6

pharyngeal arch 4

Question 7

which pharyngeal arch does the recurrent laryngeal branch of CN X come from

Answer 7

pharyngeal arch 6

Question 8

what arises from the first pharyngeal cleft (between pharyngeal arches 1 and 2 on the ectoderm (OUTER surface))

Cleft = eCtoderm

Answer 8

external auditory meatus (makes sense bc pharyngeal pouch 1 = incus and malleolus, pharyngeal pouch 2 = stapes)

Question 9

what does the utricular part of the otic vesicles give rise to

Answer 9

semi circular canals

Question 10

what does the saccular part of the otic vesicles give rise to

Answer 10

cochlea

Question 11

what arises from the 1st pharyngeal pouch (between pharyngeal arches 1 and 2 on the endoderm (INNER surface))

Answer 11

middle ear

Question 12

what type of lining surrounds the middle ear cavity (bc the middle ear cavity comes from the 1st pharyngeal pouch)

Answer 12

endoderm

Question 13

what type of lining surrounds the outer ear cavity (bc the outer ear comes from the 1st pharyngeal cleft)

Answer 13

ectoderm

pharyngeal Cleft = eCtoderm

Question 14

which pharyngeal arches supply the auricular hillocks (fuse together to form the auricle)

Answer 14

1 and 2
1st pharyngeal arch = 1-3 auricular hillocks
2nd pharyngeal arch = 4-6 auricular hillocks

Question 15

what is an extra lump of skin in front of the tragus called

Answer 15

periauricular skin tags (from auricular hillock migration)

Question 16

what is the primary palate and philtrum of the upper lip made of

Answer 16

2 nasal prominences

Question 17

what is the secondary palate of the upper lip made of

Answer 17

4 maxillary prominences

Question 18

what is the lower lip made of

Answer 18

2 mandibular processes

Question 19

what 2 cavities do the primary and secondary palates separate

Answer 19

nasal and oral cavities

Question 20

what is a cleft palate/lip a failure of

Answer 20

palate fusion (nasal or maxillary prominences)