query: instance_of oviduct
supports: The Fallopian tubes, also known as, uterine tubes, and salpinges ("singular" salpinx), are two very fine tubes lined with ciliated epithelia, leading from the ovaries of female mammals into the uterus, via the uterotubal junction. In non-mammalian vertebrates, the equivalent structures are called oviducts. Vertebrates comprise all species of animals within the subphylum Vertebrata (chordates with backbones). Vertebrates represent the overwhelming majority of the phylum Chordata, with currently about 64,000 species described. Vertebrates include the jawless fish and the jawed vertebrates, which include the cartilaginous fish (sharks and rays) and the bony fish.  The uterotubal junction or utero-tubal junction is the connection between the endometrial cavity of the uterus and the fallopian tube (uterine tube) at the proximal tubal opening, the beginning of the intramural part of the fallopian tube. Histologically, the endometrial epithelium changes over to the ciliated tubal epithelium. The uterus (from Latin "uterus", plural "uteri") or womb is a major female hormone-responsive reproductive sex organ of humans and most other mammals. In the human, the lower end of the uterus, the cervix, opens into the vagina, while the other end, the fundus, is connected to the fallopian tubes. It is within the uterus that the fetus develops during gestation. In the embryo the uterus develops from the paramesonephric ducts which fuse into the single organ known as a simplex uterus. The uterus has different forms in many other animals and in some it exists as two separate uteri known as a duplex uterus. In vertebrates , other than mammals , the passageway from the ovaries to the outside of the body is known as the oviduct . In female mammals this is known as the Fallopian tube . The eggs travel along the oviduct . These eggs will either be fertilized by sperm to become a zygote , or will degenerate in the body . Normally , these are paired structures , but in birds and some cartilaginous fishes , one or the other side fails to develop ( together with the corresponding ovary ) , and only one functional oviduct is found . Except in teleosts , the oviduct does not directly contact the ovary . Instead , the most anterior portion ends in a funnel - shaped structure called the infundibulum , which collects eggs as they are released by the ovary into the body cavity . The only female vertebrates to lack oviducts are the jawless fishes . In these species , the single fused ovary releases eggs directly into the body cavity . The fish eventually extrudes the eggs through small genital pores towards the rear of the body .
candidates: fine fish hormone junction opening organ part passageway sex organ side species two
answer: sex organ