Protozoans with no means of locomotion belong to Sporozoa.

The relatively soft skeleton of bath sponges are made of Sponging fibres.

The unique characheristic feature of coelenterates is the presence of cnidoblasts.

The nematocysts found in coelenterates are specialised structures for offence, defence and secretion.

The coelenterates are the first group of animals to have true nerve cells.

Worms of the phylum platyhelminthes are triploblastic but do not posses body cavity.

Metameres are the outer segments of the cuticle.

Round worms of the class nematoda are called dioecious because sexes are separate.

The glandular structure known as the clitellum is associated with reproduction.

The sponge skeleton is composed of structures called the spicules.

In plasmodium, the male and female gametocytes are produced by merozoites.

The defensive organelles of paramecium are called Trichocysts.

Flukes are flat worms constituting the class Trematoda.

Flame cells are ciliated structures mainly concerned with excretion in flatworms.

Multicellular animals which show active movements through their environments are characterised by the presence of bilateral symmetry.