IMMUNOLOGY

Detailed explanation-1: -Bacteria and archaea are all unicellular prokaryotes. Eukaryotes do have cell nuclei and their structures are more complex. Yeasts and algae are examples of unicellular eukaryotes. Unlike prokaryote cells, eukaryote cells have organelles, cell organs fulfilling important functions in the cell.

Detailed explanation-2: -Prokaryotes are simple organisms that lack membrane-bound organelles. All prokaryotes are unicellular. They consist of only one cell. Example: bacteria. They possess a ‘nucleoid’ instead of a true nucleus.