Branchial Arch/Branchial Pouch Path

Question 1

What is being described: Arytenoids, Cricoid, Corniculate, Cuneiform, Thyroid.

Answer 1

Cartilage of 4th-6th branchial arches

Used to sing and ACCCT!

Question 2

What is being described: Reichert cartilage: Stapes, Styloid process, lesser horn of hyoid, Stylohyoid ligament.

Answer 2

Cartilage of 2nd branchial arch

Question 3

What is being described: Greater horn of hyoid

Answer 3

Cartilage of 3rd branchial arch

Question 4

What is being described: Maxillary process (maxilla, zygomatic bone)
Mandibular process (Meckel cartilage, Mandible)
Malleus and incus, sphenomandibular ligament

Answer 4

Cartilage of 1st branchial arch

Question 5

What is being described: muscles of facial expression, Stapedius, Stylohyoid, platysma, posterior belly of digastric.

Answer 5

Muscles of 2nd branchial arch

Question 6

What is being described: Temporalis, Masseter, lateral and medial pterygoids, Mylohyoid, anterior belly of digastric, tensor tympani, anterior 2/3 of tongue, tensor veli palatini

Answer 6

Muscles of 1st branchial arch

—> muscles of mastication

Question 7

What is being described: Stylopharyngeus

Answer 7

Muscles of 3rd branchial arch

Question 8

Most pharyngeal constructors, cricothyroid, levator veli palatini

Answer 8

Muscles of 4th branchial arch

Question 9

What is being described: All intrinsic muscles of larynx except cricothyroid

Answer 9

Muscles of 6th branchial arch

Question 10

Abnormalities of Arches 3 and 4 form and cause what?

Answer 10

Posterior 1/3 of tongue.

Abnormality would be from the back of the tongue.

Question 11

Defects of 1st branchial arch cause what? What are the clinical Fx?

Answer 11

Neural crest dysfunction-1st branchial arch: mandibular hyperplasia, facial abnormalities

Question 12

What is being described and what is the etiology: micrognathia, glossitis, cleft palate, airway obstruction.

Answer 12

1st Branchial arch defect, Pierre Robin sequence

Question 13

What is being described: derives middle ear cavity, Eustachian tube, Mastoid ir cells.

Answer 13

1st branchial pouch —> contributes to endoderm-lined structures of ear.

Question 14

What is being described: derives Epithelial lining of palatine tonsil

Answer 14

2nd branchial pouch

Question 15

What is being described: derives Dorsal wings—> inferior parathyroids.
Ventral Wings—> thymus

Answer 15

3rd branchial pouch

Question 16

What structures end up below the superior parathyroids and the parafollicular (C) cells of the thyroid?

Answer 16

Third branchial pouch structures: Thymus, left and right inferior parathyroids.

3rd pouch structures end up below 4th pouch structures

Question 17

What is being described: derives Dorsal wings—> Superior parathyroids
Central Wings—> ultimobranchial body and parafollicular (C) cells of thyroid?

Answer 17

4th branchial pouch

Question 18

What is being described: Chromosome 22q11 deletion. Aberrant development of 3rd and 4th pouches—> T-cell deficiency (thymic aplasia) and hypocalcemia (failure of parathyroid development). Associated with cardiac defects (conotruncal abnormalities).

Answer 18

DiGeorge Syndrome

Question 19

What is being described: failure of fusion of the maxillary and merged medial nasal processes (formation of primary palate).

Answer 19

Cleft lip

Question 20

What is being described: failure of fusion of the two lateral palatine shelves with the nasal septum and/or median palatine shelf (formation of 2ary palate).

Answer 20

Cleft palate