Zoology · Ch 4 — Organ and Organ Systems in Animals
Reproductive System
Reproductive System
The pigeon shows a striking reproductive adaptation to flight: in the female, only the left ovary and its oviduct are functional, while the right side is reduced to a rudiment, reducing the weight the bird must carry aloft. The single functional ovary releases ova that are picked up by a funnel-like opening (ostium) at the front of the oviduct, which is regionally differentiated into the magnum, isthmus and uterus (shell gland) before opening posteriorly into the urodaeum. In the male, a pair of ovoid testes attached to the front of the kidneys by peritoneum give rise to vasa deferentia that run backward alongside the ureters and open on small papillae into the urodaeum; each vas deferens is dilated into a seminal vesicle …
What this figure shows. The female system labelling the functional left ovary with its ova, the funnel or ostium, the oviduct differentiated into magnum, isthmus and uterus (shell gland), the rudiment of the right oviduct, adrenal gland, kidney, ureter with its opening, rectum, cloaca and cloacal a …