Root of the tree

Protocell, Bacteria, Archaea, Actinobacteria, Nucleus, Animal cells, Giardia Lamblia, Chloroplasts, Excavata, Rhizaria, Chromalveolata Plant cells, Green Algae, Rhodophyta (Red Algae), Phaeophyceae (Brown Algae)

This was the hardest part of the tree for my tiny brain and I still don't understand it all, I'm not sure anyone really does. There are a few hypothesis' in there and some of them might be less likely however I have included for artistic reasons. (The Nucleus having an endosymbiotic relationship with an Archaea and the origin of Archaea)