MAHARASHTRA Class 10: Nonchordates - Acoelomates Videos | Classification of Animals

A coral is an animal organism living in colonies of polyps.

Phylum Platyhelminthes has three layers of cells such as the ectoderm, endoderm and mesoderm. 

Platyhelminths or flatworm belong to Phylum Platyhelminthes, a group of soft-bodied, much flattened invertebrates. 

Nematodes are also known as roundworms. 

Roundworms like whipworms, hookworms, pinworms and filarial worms are parasitic in humans.