Unicellular organism: Amoeba – Amoeba is a single-celled organism belonging to the domain Eukaryota. It moves by extending pseudopodia and primarily lives in freshwater environments.

Multicellular organism: Human – Humans are multicellular organisms belonging to the species Homo sapiens. They consist of trillions of specialized cells organized into tissues, organs, and organ systems, allowing for complex functions and behaviors.