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                                         The Sex Organs - The Male Sex Organs 
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                                         Some Homologous Structures 
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                                                                     Some Homologous Structures in the Female and Male Sexual Systems 
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                                                                     Before a baby boy is born, the "male" hormone testosterone transforms his originally undifferentiated embryo, leading to the development of a male body with male sex organs. In case of a baby girl, the absence of testosterone at this stage lets the embryo grow "automatically" into a female body with female sex organs. However, since both male and female sex organs derive from the same embryonic cell mass, they still correspond to each other or, in scientific language, are "homologous." 
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                                                                                 Female 
                                                                                Ovaries  Urethra Labia minora (minor lips) Labia majora (major lips) Clitoris  Bartholin's glands Paraurethral glands ("female prostate") 
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                                                                                 Male 
                                                                                Testicles Prostatic urethra Urethral tube of penis Scrotum Penis Cowper's glands Prostate   
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