Embryology USMLE Step 1 Practice Question
A 3-year-old male presents with recurrent pharyngitis and fever (temperature 38.5°C, heart rate 110/min). Physical examination reveals enlarged lymphoid masses on each side of the oropharynx between the palatoglossal and palatopharyngeal arches. Complete blood count shows leukocytosis (WBC 14,000/μL). He undergoes surgical removal of these structures. Notably, his palate is intact and he has no difficulty swallowing. These removed lymphoid tissues developed embryologically from which pharyngeal pouch?
Answer choices
- ASecondCorrect answer
- BFirst
- CFourth
- DFifth
- EThird
- FSixth
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