Pharyngeal Derivatives

Question 1

Pharyngeal Arch 1:

Cartilage Derivatives

Answer 1

The M’s and T’s

• Maxillary process
  
  • Maxilla
  • zygoMatic bone
• Mandibular Process
  
  • Meckel cartilage
  • Mandible
• Malleus
• Incus
• sphenoMandibular ligament

Question 2

Pharyngeal Arch 1:

Muscle Derivatives

Answer 2

The M’s and T’s

• Muscles of Mastication
  
  • Masseter
  • Medial ptyregoid
  • Lateral ptyregoid
  • Temporalis
• Myelohyoid
• tensor Tympani
• Tensor Veli Palantini
• Anterior Belly of the Digastric
• Ant 2/3 of Tongue

Question 3

Pharyngeal Arch 1:

Nerve Derivatives

Answer 3

The M’s and T’s

• Mandibular branch of Trigem V3
• Maxillary branch of Trigem V2
• (Chew)

Question 4

Pharyngeal Arch 2:

Cartilage Derivatives

Answer 4

S Structures

• Stapes
• Styloid Process
• Stylohyoid Ligament
• Lesser horn of hyoid

Question 5

Pharyngeal Arch 2:

Muscle Derivatives

Answer 5

S Structures

• Muscles of facial expression
• Stapedius
• Stylohyoid
• platySma
• posterior belly of digastric

Question 6

Pharyngeal Arch 2:

Nerve Derivatives

Answer 6

S Structures

• CN Seven (facial expression Smile)

Question 7

Pharyngeal Arch 3:

Cartilage Derivatives

Answer 7

Think Pharyngeal

• Greater horn of hyoid

Question 8

Pharyngeal Arch 3:

Muscle Derivatives

Answer 8

Think Pharyngeal

• Stylopharyngeus
• (forms posterior 1/3 of tongue with Arch 4)

Question 9

Pharyngeal Arch 3:

Nerve Derivatives

Answer 9

Think Pharyngeal

• Glossopharyngeal (CN 9) (innervates stylopharyngeous; swallow Styl-ishly

Question 10

Pharyngeal Arch 4:

Cartilage Derivatives

Answer 10

Think Cricoid, Thyroid, and Larynx

This also forms structures in conjunction with Arch 6

• Arytenioids
• Corniculate
• Cuniform
• Cricoid cartilage
• Thyriod cartilage
• Cartilage of larynx

Question 11

Pharyngeal Arch 4:

Muscle Derivatives

Answer 11

Think Cricoid, Thyroid, and Larynx

• Cricothyroid muscles
• Pharyngeal Muscles (pharyngeal constrictors) (Swallowing)
• Levator veli palatini
• (forms posterior 1/3 of tongue with Arch 3)

Question 12

Pharyngeal Arch 4:

Nerve Derivatives

Answer 12

Think Cricoid, Thyroid, and Larynx

This also forms structures in conjunction with Arch 6

• CN 10 (4+6=10)
  
  • Superior Laryngeal
  • (Simply Swallow)

Question 13

Pharyngeal Arch 5:

Cartilage Derivatives

Answer 13

THIS ARCH DOES NOT DEVELOP/PROGRESS

Question 14

Pharyngeal Arch 5:

Muscle Derivatives

Answer 14

THIS ARCH DOES NOT DEVELOP/PROGRESS

Question 15

Pharyngeal Arch 5:

Nerve Derivatives

Answer 15

THIS ARCH DOES NOT DEVELOP/PROGRESS

Question 16

Pharyngeal Arch 6:

Cartilage Derivatives

Answer 16

Think Cricoid, Thyroid, and Larynx

This also forms structures in conjunction with Arch 4

• Arytenioids
• Corniculate
• Cuniform
• Cricoid cartilage
• Thyriod cartilage
• Cartilage of larynx

Question 17

Pharyngeal Arch 6:

Muscle Derivatives

Answer 17

Think Cricoid, Thyroid, and Larynx

• Rest of Laryngeal Muscles (speech) not formed by Arch 4
• I.E. All intrensic muscles of the larynx EXCEPT CRICOTHYROID

Question 18

Pharyngeal Arch 6:

Nerve Derivatives

Answer 18

Think Cricoid, Thyroid, and Larynx

This also forms structures in conjunction with Arch 4

• CN 10 (4+6=10)
  
  • Reccurent laryngeal
  • Speak

Question 19

1st Pharyngeal Cleft Derivatives

Answer 19

• External auditory meatus

Question 20

2nd Pharyngeal Cleft Derivatives

Answer 20

• Temporary Cervical Sinuses
  
  • With the 3rd and 4th Clefts
  • (are eventually obliterated by proliferation of 2nd arch mesenchyme)

(If persistant → Branchial Cleft Cyst in lateral neck; anterior to sternocleidomastoid muscle and immobile during swallowing (contrasting to Thryoglossal Duct Cyst which is midline and mobile w/ swallowing))

Question 21

3rd Pharyngeal Cleft Derivatives

Answer 21

• Temporary Cervical Sinuses
  
  • With the 2nd and 4th Clefts
  • (are eventually obliterated by proliferation of 2nd arch mesenchyme)\

(If persistant → Branchial Cleft Cyst in lateral neck; anterior to sternocleidomastoid muscle and immobile during swallowing (contrasting to Thryoglossal Duct Cyst which is midline and mobile w/ swallowing))

Question 22

4th Pharyngeal Cleft Derivatives

Answer 22

• Temporary Cervical Sinuses
  
  • With the 2nd and 3rd Clefts
  • (are eventually obliterated by proliferation of 2nd arch mesenchyme)

(If persistant → Branchial Cleft Cyst in lateral neck; anterior to sternocleidomastoid muscle and immobile during swallowing (contrasting to Thryoglossal Duct Cyst which is midline and mobile w/ swallowing))

Question 23

1st Pharyngeal Pouch Derivatives

Answer 23

• Middle Ear Cavity
• Eustachian tubes
• Mastoid air cells

(contributes to the endoderm lined structures of the ear)

Question 24

2nd Pharyngeal Pouch Derivatives

Answer 24

• Epithelial lining of the palatine tonsils

Question 25

3rd Pharyngeal Pouch Derivatives

Answer 25

* Dorsal wings * Inferior parathyroid glands * Ventral wings * Thymus

Question 26

4th Pharyngeal Pouch Derivatives

Answer 26

* Dorsal Wings * Superior Parathyroid glands * Ventral Wings * Ultimobranchial body * Parafollicular (C) Cells of the Thyroid

Question 27

1^st Aortic Arch

Answer 27

* Part of Maxillary artery * (a branch of the external carotid) (1st arch is MAXimal)

Question 28

2^nd Aortic Arch

Answer 28

* Stapedial artery * Hyoid artery (Second = Stapedial)

Question 29

3^rd Aortic Arch

Answer 29

* Common Carotid artery * Proximal part of Internal Carotid artery (C is the 3rd letter of the alphebet)

Question 30

4^th Aortic Arch

Answer 30

* On Left * Aortic Arch * On Right * Proximal part of Right Subclavian (4th arch (4 limbs) = Systemic) (Right recurrent Laryngeal nerve loops around proximal right sublavian from 4th) (Left recurrent Laryngeal nerve loops around aortic arch DISTAL to ductus arteriosus (not sure if that portion of the arch is from 4th)

Question 31

6^th Aortic Arch

Answer 31

* Proximal part of pulmonary arteries (part proximal to that is from truncus arteriosus) * Ductus arteriosus (6th arch = pulmonary and the pulmonary to systemic shunt)