Branchial Arch Derivatives

Question 1

Cleft 1

Answer 1

External auditory meatus

Question 2

Pouch 1

Answer 2

Middle ear cavity

Auditory tube

Question 3

Pouch 2

Answer 3

Fossa for palatine tonsil

Question 4

Pouch 3

Answer 4

Inferior parathyroid gland

Thymus

Question 5

Pouch 4

Answer 5

Superior parathyroid gland

Question 6

Pouch 5

Answer 6

Calcitonin cells of thyroid

Question 7

Arch 1: innervation, muscles, and bones?

Answer 7

CN V
Muscles of mastication: lateral / medial pterygoids, temporalis, and masseter.
Tensor tympani, tensor veli palatini, mylohyoid, and anterior belly of digastric.
Bones: maxila, mandible, malleus, and incus

Question 8

Arch 2: innervation, muscles, and bones?

Answer 8

CN VII
Muscles of facial expression plus posterior belly of digastric, stylohyoid, and stapedius
Bones: stapes, styloid process, and lesser horn of hyoid

Question 9

Arch 3: innervation, muscles, and bones?

Answer 9

CN IX
Stylopharyngeus
Greater horn of hyoid

Question 10

Arch 4: innervation, muscles, and bones?

Answer 10

CN X (superior laryngeal nerve)
Levator veli palatini, intrinsic muscles of soft palate, cricothyroid, and pharyngeal constrictor muscles.
Thryoid cartilage

Question 11

Arch 6: innervation, muscles, and bones?

Answer 11

CN X (recurrent laryngeal nerve)
Intrinsic laryngeal muscles
Cricoid cartilage

Question 12

Preotic somites develop into?

Answer 12

Extraoccular muscles. Innervated by CN III, IV, and VI

Question 13

Postotic somites develop into?

Answer 13

Tongue muscles. Innervated by CN XII.

Question 14

Tensor tympani

Answer 14

CN V

Question 15

Tensor veli palatini

Answer 15

CN V

Question 16

Mylohyoid

Answer 16

CN V

Question 17

Anterior belly of digastric

Answer 17

CN V

Question 18

Posterior belly of digastric

Answer 18

CN VII

Question 19

Stapedius

Answer 19

CN VII

Question 20

Stylohyoid

Answer 20

CN VII