A<unk>  is a collection of cells, formed during animal embryogenesis.<unk> s are only really pronounced in the vertebrates. However, all animals more complex than sponges (eumetazoans and agnotozoans) produce two or three primary tissue<unk> s (sometimes called primary<unk> s). Animals with radial symmetry, like cnidarians, produce two called ectoderm and endoderm, making them diploblastic. Animals with bilateral symmetry produce a third<unk>  in-between called mesoderm, making them triploblastic.<unk> s will eventually give rise to all of an animal’s tissues and organs through a process called organogenesis.
Germ layer
Adnexa
Parenchyma
Serous membrane
Mesoderm
Epithelium
Neural crest
Nucleohyaloplasm