Embryology USMLE Step 1 Practice Question
After an amniocentesis, a 29-year-old woman who is carrying twins learns that one fetus has XY chromosomes and the other has XX chromosomes. At 37 weeks' gestation, the female delivers 2 healthy babies. Which of the following structures is likely to be present in the baby with the XY chromosomes but not in the one with the XX chromosomes?
Answer choices
- AMembranous urethra
- BBulbourethral glandCorrect answer
- CBulbospongiosus muscle
- DCorpus cavernosum
- EPerineal body
- FUrethral meatus
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