allantoic vesicle — n the cavity of the allantois * * * see under diverticulum … Medical dictionary
Diverticulum — A small bulging sac pushing outward from the colon wall is a diverticulum. As a person ages, pressure within the large intestine (colon) causes pockets of tissue (sacs) that push out from the colon walls. The plural is diverticula. Diverticula… … Medical dictionary
vertebrate — /verr teuh brit, brayt /, adj. 1. having vertebrae; having a backbone or spinal column. 2. belonging or pertaining to the Vertebrata (or Craniata), a subphylum of chordate animals, comprising those having a brain enclosed in a skull or cranium… … Universalium
allantois — A fetal membrane developing from the hindgut (or yolk sac, in humans). In humans it is vestigial; externally, in mammals, it contributes to the formation of the umbilical cord and placenta; in birds and reptiles, it lies close beneath the porous… … Medical dictionary
Cloaca (embryology) — For other uses, see Cloaca. Cloaca (embryology) Tail end of human embryo thirty two to thirty three days old. Cloaca is visible at center left. The endodermal cloaca is labeled with green, while the ectodermal cloaca is seen as a colorless crest… … Wikipedia