what does vagina do
The vagina is a sex organ that is part of the female genital tract. It is a muscular and tubular in structure. In humans, the vagina extends from the vulva to the uterus. The outer vaginal opening may be partly covered by a membrane called the hymen.At the deep end, the cervix (neck of the uterus) bulges into the vagina. The vagina allows for sexual intercourse and childbirth.It channels menstrual flow, which occurs periodically as part of the menstrual cycle.n its normal state, there is anatomical variation in the length of the vagina of a woman of child-bearing age. The length is approximately 7.5 cm (2.5 to 3 in) across the anterior wall (front), and 9 cm (3.5 in) long across the posterior wall (rear), making the posterior fornix deeper than the anterior.