Question

Give any one difference between protozoa and metazoan.

Answer 1

Hint: The Protozoa belongs to the kingdom Protista while Metazoa belongs to the kingdom Animalia. Protozoa and Metazoa are eukaryotic organisms and their classification is based on their body organization.

Complete answer:
Protozoa belongs to Kingdom Protista marked by a single-celled structure. Most of the members of these groups are pathogenic. Example- Plasmodium, E. histolytica. It includes Amoeba, flagellates, ciliates, and Sporozoa.
Metazoa represents a group of multicellular animals. Example- Fish, Mammals, Spider, etc. They show cellular level, tissue level, and organ system level of organization. Metazoans are classified into two main forms: vertebrates and invertebrates.

Additional information:
Similarities between Protozoa and Metazoa are:
a. They are eukaryotic organisms
b. They have a nucleus inside their cells.
c. They lack a cell wall.
d. Don’t perform photosynthesis.
e. Energy needs for their cellular processes are derived from the chemical energy of nutrients.
Difference between protozoa and metazoa

Protozoa	Metazoa
They are unicellular	They can be both unicellular and multicellular
Body form is microscopic	Body form can be microscopic as well as macroscopic.
No division of labour found i.e. a single cell performs all the metabolic activities like respiration, digestion, reproduction, etc.	Different cells perform different activities, so division of labour exists.
Level of organization- cellular	Level of organization- Cellular (sponges), Tissue (cnidarians), Organ system (Aschelminthes to Chordata)
Example- Amoeba, Euglena, Paramecium, Plasmodium.	Example- Spider, Starfish, Octopus, Gorilla

Note: Protozoans belong to the kingdom Protista while metazoans belong to kingdom Animalia. Protozoans reproduce sexually and asexually while majority metazoans undergo sexual reproduction. Evolutionarily metazoans developed from the protozoans.