1. Microorganisms that are similar to bacteria in size and simplicity of structure but radically different in molecular organization.
2. A member of a large group of unicellular microorganisms which have cell walls but lack organelles and an organized nucleus.
3. All the kingdoms of eukaryotic, including fungi, plantae, and animalia are placed in the domain eukarya.
4. Is the highest taxonomic rank in the hierarchical biological classification system, above the kingdom level.
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