what is the difference a blastula and gastrula
â¢ Three primary germ layers are present in gastrula unlike in the blastula. â¢ Blastula is often called a pre-embryo, whereas gastrula is referred to as a mature embryo. â¢ Gastrula has more cells than blastula.he three germ layers of gastrula interact in various ways to form organs, hence called organogenesis. Since, blastula and gastrula occur separately as different structures in different phases, there are some differences can be observed between both structures. Blastula.