Development of the Head and Neck

Question 1

How many pharyngeal arches are there?

Answer 1

5 (1,2,3,4,6)

Question 2

Which cranial nerve is associated with the 1st pharyngeal arch?

Answer 2

Trigeminal (CN V)

Question 3

Which cranial nerve is associated with the 2nd pharyngeal arch?

Answer 3

Facial (CN VII)

Question 4

Which cranial nerve is associated with the 3rd pharyngeal arch?

Answer 4

CN IX

Question 5

Which cranial nerve is associated with the 4th pharyngeal arch?

Answer 5

CN X (superior laryngeal)

Question 6

Which cranial nerve is associated with the 6th pharyngeal arch?

Answer 6

CN X (recurrent laryngeal)

Question 7

Which cartilage is associated with the 1st pharyngeal arch?

Answer 7

Meckel’s cartilage (becomes mandible)

Question 8

Which cartilage is associated with the 2nd pharyngeal arch?

Answer 8

Reichert’s cartilage (stapes, hyoid bone)

Question 9

Which cartilage is associated with the 4th and 6th pharyngeal arches?

Answer 9

Cartilages of larynx

Question 10

What does the 1st pharyngeal pouch become?

Answer 10

Eustachian tube and middle ear cavity

Question 11

What does the 2nd pharyngeal pouch become?

Answer 11

Palatine tonsil

Question 12

What do the 3rd and 4th pharyngeal pouches become?

Answer 12

PTH gland and thymus

Question 13

What does the 1st pharyngeal cleft become?

Answer 13

External auditory meatus

Question 14

How many cranial nerves are associated with pharyngeal arches?

Answer 14

4 - (CNs V, VII, IX and X)

Question 15

What are muscles of mastication derived from?

Answer 15

Ph Arch 1

Question 16

What are muscles of facial expression derived from?

Answer 16

Ph Arch 2

Question 17

What is stylopharyngeus derived from?

Answer 17

Ph Arch 3

Question 18

What is cricothyroid and pharyngeal constrictor muscles derived from?

Answer 18

Ph Arch 4

Question 19

What muscles are derived from Ph Arch 6?

Answer 19

Intrinsic muscles of the larynx

Question 20

Describe the origins of the pituitary gland

Answer 20

Rathke’s pouch - ectoderm - AP

Infudibulum - neuroectoderm - PP

Question 21

What embryonic structures contribute to the development of the face?

Answer 21

Frontonasal prominence and the 1st and 2nd Ph Arches

Question 22

What structures in the developing face must fuse to form the upper lip and jaw?

Answer 22

Frontonasal prominence and medial nasal prominence

Question 23

How does cleft lip and palate arise?

Answer 23

Failure of the frontonasal prominence to fuse with maxillary prominence

Question 24

How is Treacher-Collins syndrome inherited?

Answer 24

Autosomal dominant

Question 25

How is Treacher-Collins syndrome characterised?

Answer 25

Hypoplasia of mandible and facial bones

Question 26

What is Di-George syndrome?

Answer 26

Congenital thymic aplasia and absence of parathyroid glands (3rd and 4th Ph Arches involved)