The Vagina Flashcards
The vagina forms the entrance
into the female reproductive tract.
The vagina consists of a
muscular canal approximately 10 cm in length that connects the uterus to the exterior.
The superior portion of the vagina is called
the fornix and meets the protruding uterine cervix.
The vaginal wall is lined by
an outer fibrous adventitia and is amazingly elastic
The vaginal wall functions as:
A. the birth canal during parturition
B. an excretory duct for the passage of menstrual components
C. the site of sperm deposition after coitus
Smooth muscle layers lie
under the inner mucosal layer and are arranged in poorly defined
circular and longitudinal layers with the majority of the fibers orientated longitudinally.
The smooth muscle assists in the:
parturition process and in the subsequent involution of the vagina after parturition.
During colitis, involuntary contraction of the smooth muscle
ensures semen will pool in the less hostile cervical region of the vagina.
Mucosal layer is the inner layer of the vagina which is composed of
mostly of a non-secretory stratified squamous epithelium.
Epithelial cells of the vagina
release glycogen into the lumen
The vagina is home to beneficial microorganisms in particular bacterial flora that help to
protect against infection by pathogenic bacteria, yeast and other organisms that may enter the vagina
In a healthy woman the predominant type of vaginal bacteria is from the genus
Lactobacillus
Lactobacillus metabolizes
the epithelial glycogen and secretes lactic acid maintaining an acidic pH (< 4.5) and thus a hostile environment for most pathogens and sperm.
The secretions of the cervix contain
buffers that neutralize the acidic environment of the vagina resulting in an increasing pH gradient from the external opening of the vagina (pH 4 to 5) to the opening of the cervix (pH 6 to 7). The pH of the cervix is 7 to 8.
The external opening of the vagina has a pH of
4 to 5
The opening of the cervix is pH
6 to 7
The pH of the cervix is
7 to 8.
