POUL 4060 Lecture Notes - Lecture 20: Yolk Sac, Allantois, Hypoblast

• School: University of Georgia
• Department: Poultry Science
• Course: POUL 4060
• Professor: Davis

Document Summary

**membranes inside embryo of growing egg: yolk sac membrane (inner layer, vitally important for survival in avian species, vascular membrane that covers the yolk, site in egg laying species for initial rbc development. Inner layer endoderm (from hypoblast) outer later mesoderm: the endoderm laying adjacent to the yolk made up of special glandular and absorbing epithelium. It provides the enzymatic capability to break down protein and lipid: connection forms with the albumin that facilitates absorption of protein and water of albumin. Very similar across species: ammonic sac- critical environment for protection, etc, formed from the same membrane (ectoderm and mesoderm, amnion is the inner membrane containing amniotic fluid in which the embryo floats and moves (cushions) Amnion & chorion were formed from same membrane: chorion (outer membrane, chorion is the outer membrane in contact with the inner shell membrane and is avascular, amniotic fluid, embryo swallows prior to hatch.