•Germinal layers are those which formed during the process of gastrulation period .
•The outer layer of germ is known ectoderm, the middle is endoderm and the innermost is the endoderm layer. •Coelomates are the organisms possessing coeloms.
• Coelom is the body cavity lie by the mesoderm.
•Examples of coelomates are Annelida, Mollusca, arthropods, etc.
• The organisms with absent coelom are called coelomates.
•E.g. Platyhelminthes.
•Some of the organisms do not have a lining by mesoderm. But it will be in the form of a scattered pouch in between ectoderm and endoderm. Such a body cavity is called pseudocolour and animals possessing pseudocoelom are referred to as pseudocoelomates
•e.g., Ascaris.