Question

How is metazoan classified?

Answer 1

Metazoan are the organisms that comprise all animals having the body composed of cells differentiated into tissues and organs and usually a digestive cavity lined with specialized cells.

Classification of Metazoan:

Metazoan is classified into two types based on the extent and type of their body design :

1. Parazoa- Parazoa are animals whose body consists of loosely aggregated cells with poorly differentiated tissues, organs and organ system. Example: Porifera.
2. Eumetazoa - Eumetazoa are animals whose tissue is organized into true tissues and there is a development of organs. Example: Ctenophora, Platyhelminthes, mammals, etc.