Ectoderm,mesoderm (middle layer) and endoderm (most proximal layer).
Each of the three primary germ layers will form a different set of specific organs and tissue types in the animal. The ectoderm will form the nervous system, the epithelial cells of the mammary glands, the lens of the eyes, hair, pigment cells and the epidermis of the skin. These three layers, the endoderm, the ectoderm and the mesoderm, are called the primary germ layers. After gastrulation, the cup-like embryonic stage that contains at least two distinct germ layers is called the gastrula. A germ layer is a primary layer of cells that form during embryogenesis. The three germ layers in vertebrates are particularly pronounced; however, all eumetazoans, (animals more complex than the sponge) produce two or three primary germ layers. Animals with radial symmetry, like cnidarians, produce two germ layers (the ectoderm and endoderm) making them diploblastic. Germ Layers. by Kate MacCord Keywords: Germ layer theory, mesoderm, endoderm, ectoderm. A germ layer is a group of cells in an embryo that interact with each other as the embryo develops and contribute to the formation of all organs and tissues. All animals, except perhaps sponges, form two or three germ layers. The germ layers develop early in embryonic life, through the process of gastrulation. During gastrulation, a hollow cluster of cells called a blastula reorganizes into two primary germ layers: an inner layer, called endoderm, and an outer layer, called germ layer (germ cell layer) any of the three primary layers of cells formed in the early development of the embryo (ectoderm, entoderm, and mesoderm), from which the organs and tissues develop. the thin middle gray layer of the cortex of the cerebellum, consisting of a single layer of Purkinje cells. germ layer. any of the three primary layers of cells formed in the early development of the embryo (ectoderm, entoderm and mesoderm), from which the organs and tissues develop. germinative layer. any proliferative layer such as the basal layer of the epidermis or the lower layer of the claw, from which the claw grows Best Answer: The purpose of gastrulation is to position the 3 embryonic germ layers, the endoderm, ectoderm and mesoderm. These layers later develop into certain bodily systems.  From Wikipedia, the free encyclopedia. Ectoderm is one of the three primary germ layers in the very early embryo. The other two layers are the mesoderm (middle layer) and endoderm (most proximal layer), with the ectoderm as the most exterior (or distal) layer. It emerges and originates from the outer layer of germ cells. germ layer. endoderm and adjacent germ layers. n. Any of the three primary cellular layers, the ectoderm, endoderm, or mesoderm, into which most animal embryos differentiate and from which the organs and tissues of the body develop. the thin middle gray layer of the cortex of the cerebellum, consisting of a single layer of Purkinje cells. germ layer. any of the three primary layers of cells formed in the early development of the embryo (ectoderm, entoderm and mesoderm), from which the organs and tissues develop. germinative layer. any proliferative layer such as the basal layer of the epidermis or the lower layer of the claw, from which the claw grows
http://study.com/academy/lesson/gastrulation-and-the-3-germ-layers-ectoderm-endoderm-mesoderm.html https://en.wikipedia.org/wiki/Germ_layer http://embryo.asu.edu/pages/germ-layers http://medical-dictionary.thefreedictionary.com/germ+layer https://answers.yahoo.com/question/index?qid=20080902143828AAed2Qe https://en.wikipedia.org/wiki/Ectoderm http://medical-dictionary.thefreedictionary.com/germ+layer
what are the primary germ layers