Early development of Drosophila
Early cleavages in the development of Drosophila produce a syncitium, in which the nuclei divide but the cytoplasm does not [top]. Cellularization (formation of complete cell membranes) subsequently produces a monolayer of cells (blastoderm) surrounding a yolk. This blastula is a ball of cells that resembles that of vertebrate animals, but has been formed by a very different process.
All text material © 2007 by Steven M. Carr