What is another word for protosome?
Pronunciation: [pɹˈə͡ʊtə͡ʊsˌə͡ʊm] (IPA) 
Protosome is a term used to describe a specific type of organism in the animal kingdom, characterized by its mode of embryonic development. Some synonyms for protosome include the terms "protozoa," "invertebrates," and "coelomates." These synonyms reference the fact that protosomes lack a spinal column and instead have a body cavity, or coelom. Additionally, many protosomes are invertebrates, meaning they lack a backbone, and some are classified as protozoa, single-celled organisms that are often classified in the same phylum as protosomes. Other related terms include "blastopore," a term used to describe the opening that forms during early embryonic development, and "metameric," which refers to segmented body structures found in some protosomes.
