It is a marine cnidarian. It includes both the modes of sexual as well as asexual form of reproduction. It shows the phenomena of polymorphism and is carnivorous. It has a pneumatophore which resembles a bladder. It has a gas plant which secretes ...

Hydra is a fresh water cnidaria which has lakes and ponds as their habitat. It consists of tentacles, mouth, manubrium, stomach, testes, bud, peduncle and basal disc. The tentacles help to catch the prey. It is sedentary and moves by looping and somersaulting. Their mode ...

It is classified on the basis of polypoid phase in the life cycle. They are classified as - hydrozoa, scyphozoa and anthozoa. The hydrozoa are also known as water animals. They are marine and occur in fresh water also. They may occur alone or in ...

These are also known as the sting cells. Their stinging nature was discovered by Aristotle. They provide the link between animals and plants. Peyssonel and Trembley grouped them as animals. Coelenterates were put together with the sponges by Leuckart. They were further divided into ...

The phylum porifera has three classes which are calcarea, hyalospongiae and demospongiae. The calcarea are also known as lime sponge. They have spicules which are calcareous in nature. They have collared flagellate cells. They are mainly marine in their habitat. The hyalospongiae are also known ...

Porifera are also known as pore bearing organisms. They are also known as sponges. The sponges were recognized by Ellis and Aristotle was the first one to identify it. They were included as animals and were given the name porifera by Robert Grant. Sometimes they ...