Algae and Protozoa are two examples of organisms that belong to the same kingdom. Both belong to the kingdom Protista. And since they are from the same kingdom, they are very similar based on some properties that are common between them. They are eukaryotic organisms because they cannot be regarded as an animal, plants, or fungus. Algae are photosynthetic organisms, and as a result, they can produce their own food. Protozoa, on the other hand, are nonphotosynthetic organisms or animal-like protists that feed only on small organisms.
They move only by using pseudopods, cilia, or flagella. Protozoa are shapeless organisms, and they are unicellular organisms, and that's why before you can have a good look at them, you need a microscope. Algae, on the other hand, look like green, and that's why there is the presence of chlorophyll in their cells. They are mostly seen and found floating on water.
The significant difference between algae and protozoa is that algae are autotrophic plant-like eukaryotes, while protozoa are heterotrophic animal-like eukaryotes that belong to the kingdom Protista. Algae are a large group of organisms, which are significant biologically. They are often photosynthetic eukaryotes existing in the water. Algae reside in both marine and freshwater.
They lack real stems, leaves, or roots, and their body looks like a thallus. There are also different colored algae, which includes a wide array of colors, including green, brown, and red algae. Almost all algae are well adapted to life in the water. An example of protozoans is Amoeba, and it is marine and free living. Algae are unicellular or multicellular plant-like organisms. Protozoans are unicellular animal-like organisms.
Algae and protozoa are two types of organisms that belong to the kingdom Protista. They have a membrane-bound nucleus since they are eukaryotic organisms and both can be unicellular. They have a difference, however, that make them distinct from each other. Protozoa are heterotrophic, meaning they utilize organic as their source of carbon since they are unable to fix carbon that is inorganic.
Algae, on the other hand, are autotrophic; they can gain organic nutrients from simple inorganic substances such as carbon dioxide. Protozoa do not contain chlorophyll so they ingest food particles by phagocytosis while algae contain chlorophyll thus they are able to produce their own food by the process of photosynthesis. Protozoa can cause certain diseases in humans whereas algae may produce toxins that can be harmful to humans and other organisms as well.