The organisms that appeared first were bacteria and blue-green algae, which are prokaryotic cells, that is, unicellular organisms without a distinct nucleus.
(The organisms; appeared; T:first) (The organisms that appeared first; were; bacteria and blue-green algae) (blue-green algae; are; prokaryotic cells)
The organisms The organisms that appeared first blue-green algae
appeared were are
T:first
bacteria and blue-green algae
prokaryotic cells