A germ layer, occasionally referred to as a germinal epithelium, is a group of cells, formed during animal embryogenesis. Germ layers are particularly pronounced in the vertebrates; however, all animals more complex than sponges (eumetazoans and agnotozoans) produce two or three primary tissue layers (sometimes called primary germ layers). Animals with radial symmetry, like cnidarians, produce two germ layers (the ectoderm and endoderm) making them diploblastic. Animals with bilateral symmetry produce a third layer between these two layers (appropriately called the mesoderm) making them triploblastic. Germ layers eventually give rise to all of an animal's tissues and organs through the process of organogenesis.
The tongue is derived from the ectoderm germ layer during early embryonic development.
Ectoderm
Nervous tissue is derived from the ectoderm germ layer during embryonic development.
The primary germ layer that forms the brain and spinal cord is called the ectoderm.
The three primary germ layers in the gastrula are the ectoderm (outer layer), mesoderm (middle layer), and endoderm (inner layer). Each layer gives rise to different tissues and organs in the developing embryo.
Gastrulation is first step towards germ layer development .
The tongue is derived from the ectoderm germ layer during early embryonic development.
Melanocytes are derived from the neural crest, which is a transient embryonic structure that forms from the ectoderm germ layer.
endoderm
Ectoderm
The primary germ layer that forms the brain and spinal cord is called the ectoderm.
Nervous tissue is derived from the ectoderm germ layer during embryonic development.
If your question is 'Is the trophoblast present during germ layer formation (i.e. gastrulation) ?' then the answer is YES
The three primary germ layers in the gastrula are the ectoderm (outer layer), mesoderm (middle layer), and endoderm (inner layer). Each layer gives rise to different tissues and organs in the developing embryo.
The middle germ layer is called mesoderm. It gives rise to structures like muscles, bones, and the circulatory system in the developing embryo.
Mesoderm forms muscles .
The endoderm is the germ layer that will become the inner lying of the body cavity as well as on the surface of the organs. Meaning of endoderm is: Endo- = within, plus derm = germ or from.