Lecture 5

Question 1

What structure does the dorsal part of the 1st pharyngeal groove form?

A) External auditory meatus
B) Tympanic cavity
C) Eustachian tube
D) Tonsillar sinus

Answer 1

A) External auditory meatus

Question 2

The fusion of the dorsal extremities of the 1st and 2nd pharyngeal arches forms which of the following structures?

A) Mastoid antrum
B) Pinna
C) Pharyngeal tonsil
D) Parathyroid gland

Answer 2

B) Pinna

Question 3

The distal part of the tubotympanic recess contributes to the development of which structure?

A) Middle ear cavity
B) Auditory tube
C) Tympanic membrane
D) Mastoid antrum

Answer 3

C) Tympanic membrane

Question 4

The cavity of the tubotympanic recess eventually forms which of the following?

A) Tonsillar crypts
B) External auditory meatus
C) Primitive tympanic cavity
D) Ultimobranchial body

Answer 4

C) Primitive Tympanic cavity

Question 5

What is the fate of the anterior extension of the 2nd pharyngeal pouch?

A) It forms the thymus
B) It forms the tonsillar sinus
C) It forms the eustachian tube
D) It forms the auditory meatus

Answer 5

B) it forms the tonsillar sinus

Question 6

Which structure will the dorsal region of the 3rd pharyngeal pouch form?

A) Superior parathyroid glands
B) Inferior parathyroid glands
C) Thymus
D) Tonsillar crypts

Answer 6

B) Inferior Parathyroid gland

Question 7

During the 6th week, the ventral region of the 3rd pharyngeal pouch gives rise to which structure?

A) Inferior parathyroid gland
B) Superior parathyroid gland
C) Thymus
D) Tonsillar crypts

Answer 7

C) Thymus

Question 8

In the 4th pharyngeal pouch, which structure begins to develop at the start of the 5th week?

A) Inferior parathyroid glands
B) Superior parathyroid glands
C) Tonsillar crypts
D) Thymus

Answer 8

B) Superior parathyroid glands

Question 9

What structure does the ultimobranchial body, derived from the 5th pharyngeal pouch, give rise to?

A) Inferior parathyroid glands
B) Parafollicular (C) cells of the thyroid gland
C) Thymus
D) External auditory meatus

Answer 9

B) Parafollicular (C) cells of the thyroid gland

Question 10

DiGeorge syndrome results from the lack of development of which pharyngeal pouches?

A) 1st and 2nd
B) 2nd and 3rd
C) 3rd and 4th
D) 4th and 5th

Answer 10

C) 3rd and 4th