The vagina is an elastic, muscular canal in the female reproductive system. It extends from the vulva to the cervix.

• Structure: It is lined with mucous membrane and contains folds called rugae, which allow it to expand.
• Function: It serves as the receptacle for the penis during sexual intercourse, the pathway for childbirth, and the route for menstrual flow.

For more detailed information, you can refer to these resources:

1. Planned Parenthood - What is a Vagina?
2. Mayo Clinic - Female Reproductive System Anatomy