by Elio — You may have heard that the small­est free-liv­ing eu­kary­ote is Os­tre­o­coc­cus tauri. So they say. O. tauri is in­deed a tiny green alga. It is en­dowed with just one chloro­plast, one mi­to­chon­drion, a Golgi body, and not much cy­to­plasm. Some­times it is only 1.0 μm in di­am­e­ter...