Are bacteria similar to and different from protozoans?

Bacteria are prokaryotes, meaning they have no membrane-bound nuclei, or organelles. They are also single celled, and typically autotrophic, which means that is can make its own food.

Protozoa are eukaryotic organisms, meaning they have a membrane-bound nucleus. It is also single celled, but it is a heterotroph, meaning it cannot make its own food.