Reproductive system Human vestigiality

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genitalia

in internal genitalia of each human sex, there residual organs of mesonephric , paramesonephric ducts during embryonic development:



gartner s duct
epoophoron
vesicular appendages of epoophoron
paroophoron

human vestigial structures include leftover embryological remnants once served function during development, such belly button, , analogous structures between biological sexes. example, men born 2 nipples, not known serve function compared women. in regards genitourinary development, both internal , external genitalia of male , female fetuses have ability or partially form analogous phenotype of opposite biological sex if exposed lack/overabundance of androgens or sry gene during fetal development. examples of vestigial remnants of genitourinary development include hymen, membrane surrounds or partially covers external vaginal opening derives sinus tubercle during fetal development , homologous male seminal colliculus. researchers have hypothesized persistence of hymen may provide temporary protection infection, separates vaginal lumen urogenital sinus cavity during development. other examples include glans penis , clitoris, labia minora , ventral penis, , ovarian follicles , seminiferous tubules.








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