BIOL 3156 Study Guide - Vigna Mungo, Metabolic Waste, Blastula
Document Summary
Meroblastic dicoidal cleavage pattern cleavage is initially incomplete. The egg is a very large, yolky egg that displaces to one side of the cytoplasm. Initially produces a subgerminal cavity this is not analogous to the blastocoel. Must establish a two layered blastoderm before gastrulation defines a blastocoel cavity. This is distinctly different from the subgerminal cavity. Resembles gastrulation in both the fishes and in mammals. The cells gradually begin to define themselves as they produce a membrane across the yolk layer. There is going to be a clear space that opens up this is referred to as the area pellucida. At one edge of the egg, there is a group of cells that begin to proliferate that is referred to as the posterior marginal zone. It will ultimately elaborate the next layer of cells it will split the subgerminal cavity in half. Area over the subgerminal cavity is the area pellucida (semitransparent) Area at marginal zones overlie yolk area opaca.
