What type of organism is an amoeba?

An amoeba is classified as a protist because it belongs to the Kingdom Protista, which includes a diverse group of unicellular organisms. Protists are primarily characterized by their eukaryotic cellular structure, meaning their cells contain a nucleus and other membrane-bound organelles. Amoebas, specifically, are known for their ability to change shape due to their flexible cell membrane and cytoplasmic extensions called pseudopodia, which they use for movement and feeding. This flexibility and method of locomotion set them apart from other categories like plants, bacteria, and fungi, which have more rigid structures and defined roles in ecosystems.

Plants are multicellular and primarily photosynthetic, bacteria are unicellular prokaryotes lacking a nucleus, and fungi have cell walls made of chitin and are typically decomposers. In contrast, the characteristics of amoebas align clearly with those of protists, justifying why the correct classification is as a protist.