Oviduct
From Biocrawler, the free encyclopedia.
In oviparous animals (those that lay eggs), the passage from the ovaries to the outside of the body is known as the oviduct. The eggs travel along the oviduct.
Oviduct of a laying hen
1 Infundibulum, 2 Magnum, 3 Isthmus, 4 Uterus, 5 Vagina with egg inside
1 Infundibulum, 2 Magnum, 3 Isthmus, 4 Uterus, 5 Vagina with egg inside
The oviduct in birds is divided in several parts:
- Infundibulum (formation of Chalazae, place of fertilization)
- Magnum (formation of egg white)
- Isthmus (formation of the shell membrane)
- Uterus (formation of egg shell)
- Vagina (formation of cuticula)
In mammals, which evolved from reptiles, the oviduct turned into the Fallopian tubes, the uterus and the vagina. The eggs don't travel all the way, but stay in the uterus. In these animals, the term oviduct should not be used.
