The body of the coelenterates consists of two layers of cells – ectoderm and endoderm, between which there is a more or less developed non-cellular layer called mesoglea. They only have one cavity called the intestinal or gastric cavity. All coelenterates are aquatic, with the exception of a few species, marine organisms. Their body is built according to the type of radial-axial symmetry.
Remember: The process of learning a person lasts a lifetime. The value of the same knowledge for different people may be different, it is determined by their individual characteristics and needs. Therefore, knowledge is always needed at any age and position.