What is the difference between the Protozoa and Metazoa?

Protozoa:

1. They are single celled organisms.

2. 2. A single cell performs all functions; therefore there is no division of labour.

3. They have a cellular grade of organization, e.g. Amoeba paramecium.

Metazoa:

1. They are multi-cellular organisms.

2. They show division labour as different cells or organs perform different functions.

3. They have cellular tissue, organ and system grade of organization, e.g Sponges to chordates.