Formation of Germinal Layers in Various Vertebrates
Learn about the comparison of formation of germinal layers in various vertebrates. Comparison: Vertebrate # Branchiostoma: 1. The egg is teleolecithal, i.e. provided with a little yolk and covered by two thin membranes, the outer vitelline and the inner perivitelline membrane. Impregnation is external. 2. Segementation - Segmentation is holoblastic but slightly unequal. The first cleavage takes palce along the [...]