Which structure serves as the passageway for sperm to enter the uterus?

The cervix serves as the passageway for sperm to enter the uterus. Located at the lower end of the uterus, the cervix connects the uterus to the vagina. During sexual intercourse, sperm are deposited in the vagina and must swim through the cervix to reach the uterus and then potentially the oviducts for fertilization. The structure is designed to allow the passage of sperm while also playing a role in protecting the uterus from infections and providing a barrier during different stages of the reproductive cycle. In contrast, the oviduct is where fertilization typically occurs, the ovary is responsible for producing eggs and hormones, and the uterus is the cavity that supports a developing fetus but is not the direct passageway for sperm.