Embryology

Question 0

2nd Pharyngeal Arch

Answer 0

CN VII - Facial

Muscles of Facial Expression - posterior digastric, stylohyoid, stapedius

Question 1

1st Pharyngeal Arch

Answer 1

CN V - Trochlear
Muscles of Mastication - mylohyoid, anterior digastric, tensor tympani, tensor veli palatini & maxillary a./ECA
Skeletal muscle innervation SVE

Question 2

3rd Pharyngeal Arch

Answer 2

CN IX - Glossopharyngeal
Stylopharyngeus
Common & ICA

Question 3

4th & 6th Pharyngeal Arch

Answer 3

CN X - Vagus
Soft palate, pharynx, largynx, stratified esophageal muscle
Thoracic derivatives of aortic arches
Cartilage - thryoid, cricoid

Question 4

GSA

• Detects what?
• Receptor origin

Answer 4

• Pain, T, P, Proprioception
• Ectoderm (*Exception = Mesoderm; GTO, proprioception w/n muscle)

Note: “general” = cranium & body

Question 5

GVA

• Detects what?
• Receptor origin

Answer 5

• Visceral sensation
• Endoderm (*Exception = splanchnic mesoderm associated with endoderm; carotid sinus, carotid body)

Note: “general” = cranium & body

Question 6

Special Sense Origin

Answer 6

Derived from ectodermal (neurogenic) placodes NOT neural crest cells

Question 7

Olfactory Placodes

• 3 letter code
• CN
• Function

Answer 7

• SVA
• CN 1 (Olfactory)
• Smell

Note: Special Visceral = chemo-receptor associated

Question 8

Epibranchial Placodes

• 3 letter code
• CN
• Function

Answer 8

• SVA (on branchial arches)
• CN VII (7 - Facial), CN IX (9-Glossopharyngeal), CN X (10-vagus)
• Taste

Note: Special Visceral = chemo-receptor associated

Question 9

Otic Placodes

• 3 letter code
• CN
• Function

Answer 9

• SSA
• CN VIII (8-Vestibulocochlear) *CN II (2-Optic) also SSA
• Auditory *Visual

Note: Special Somatic = associated with photon, vibration, gravity, force (NOT a chemical)