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Chapter 16. Male Reproductive System
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Refer to the micrograph below to answer the following question. The lower panel of the micrograph shows a small region of the organ at high magnification.
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After reviewing a biopsy specimen, the pathologist diagnoses the tumor as originating from the cells labeled A. Which of the following substances would most likely be secreted by the cells in this tumor?
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A. Androgen-binding protein
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The answer is E: The cells labeled A in the micrograph are Leydig cells in the interstitium between the seminiferous tubules of the testis. Leydig cells normally synthesize and release the androgen testosterone.
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Refer to the micrograph below to answer the following question. The lower panel of the micrograph shows a small region of the organ at high magnification.
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Which letter designates the type of cell that forms the blood-testis barrier?
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The answer is C: The cell labeled C is a Sertoli cell, a nonproliferating support cell in the seminiferous epithelium of the testis. Tight junctions between Sertoli cells form the blood-testis barrier, which prevents sperm-specific antigens from entering the blood and becoming immunogens, and prevents circulating antibodies from entering the tubule lumen. Sertoli cells also secrete a fructose-rich fluid that nourishes developing sperm and facilitates transport of sperm to the genital ducts, androgen-binding, which binds testosterone and increases the concentration of testosterone in the tubule lumen, and inhibin and activin.
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Which organ listed below produces a fructose-rich fluid that comprises almost all of the ejaculate?
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The answer is D: The seminal vesicles are two highly convoluted, unbranched tubules that secrete a thick, creamy fluid that comprises 70–80% of the ejaculate. The secretions contain a high concentration of fructose, which provides an energy source for sperm and nourishes sperm within the female reproductive tract.
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Arrange in order the following structures and organs that a spermatozoon passes through ...