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What is Lower 1/3 of vagina is formed by and explain in detail?
Lower 2/3rd of vagina formed from sinovaginal bulb which comes from endoderm of urogenital sinus. Upper 1/3rd of vagina is derived from fused paramesonephric duct. Mesonephric duct forms the collecting pa or ductular pa of male reproductive system. Mesoderm of Mullerian duct is basically paramesonephric duct.