which kingdom is composed of eukaryotes which are mostly unicellular that can be heterotrophs or autotrophs?
Organisms composed of eukaryotic cells are divided into 4 main groups: 1  Protista are mostly unicellular or colonial eukaryotes. 2  They may be either photosynthetic autotrophs or heterotrophs. 3  This is a very diverse group that is actually composed of multiple kingdoms.