WBR0337
| Author | [[PageAuthor::Rim Halaby, M.D. [1] (Reviewed by Alison Leibowitz)]] |
|---|---|
| Exam Type | ExamType::USMLE Step 1 |
| Main Category | MainCategory::Physiology |
| Sub Category | SubCategory::Genitourinary |
| Prompt | [[Prompt::During development, testosterone secreted in-utero by the testes plays an important role in the differentiation of external and internal male organs by acting directly on the Wolffian ducts. Similarly, dihydrotestosterone (DHT), a more potent androgen produced from testosterone by the action of 5-alpha-reductase, is also involved in the differentiation of male organs. Which of the following processes is most likely achieved by the action of DHT?]] |
| Answer A | AnswerA::Differentiation of the epididymis |
| Answer A Explanation | AnswerAExp::Differentiation of the epididymis is achieved by the action of testosterone. |
| Answer B | AnswerB::Differentiation of the vas deferens |
| Answer B Explanation | AnswerBExp::Differentiation of the vas deferens is achieved by the action of testosterone. |
| Answer C | AnswerC::Closure of the epiphyseal plate |
| Answer C Explanation | AnswerCExp::Closure of the epiphyseal plate is achieved by the action of testosterone. |
| Answer D | AnswerD::Differentiation of the prostate gland |
| Answer D Explanation | AnswerDExp::Differentiation of the prostate gland is achieved by the action of DHT. |
| Answer E | AnswerE::Pubertal voice deepening |
| Answer E Explanation | AnswerEExp::Pubertal voice deepening is achieved by the action of testosterone. |
| Right Answer | RightAnswer::D |
| Explanation | [[Explanation::In males, testosterone is involved in the differentiation of internal genitalia (excluding the prostate), voice deepening, and closure of the epiphyseal plates of bones. Growth spurt at puberty is also due to the action of testosterone, including the pubertal growth of the penis, seminal vesicles, and production of sperm. On the other hand, dihydrotestosterone is involved early in the differentiation of the external genitalia, i.e. the penis and the scrotum, and the prostate. Later, it is involved in the growth of the prostate, balding, and activity of sebaceous glands. Educational Objective: DHT is involved in the differentiation of the external genitalia, i.e. the penis and the scrotum, and the prostate. |
| Approved | Approved::Yes |
| Keyword | WBRKeyword::Differentiation, WBRKeyword::sex organs, WBRKeyword::testosterone, WBRKeyword::DHT, WBRKeyword::dihydrotestosterone, WBRKeyword::epididymis, WBRKeyword::vas deferens, WBRKeyword::genitals, WBRKeyword::genitalia, WBRKeyword::puberty, WBRKeyword::pubertal, WBRKeyword::penis, WBRKeyword::sperm, WBRKeyword::sebaceous, WBRKeyword::hormone, WBRKeyword::hormones |
| Linked Question | Linked:: |
| Order in Linked Questions | LinkedOrder:: |