He endosymbiotic theory hypothesizes that mitochondria and chloroplasts were formed when cells were engulfed by larger cells that were precursors to cells.

The endosymbiotic theory hypothesizes that mitochondria and chloroplasts were formed when prokaryotic cells were engulfed by larger cells that were precursors to eukaryotic cells.

prokaryotic ; eukaryotic

He endosymbiotic theory hypothesizes that mitochondria and chloroplasts were formed when prokaryotic cells were engulfed by larger cells that were precursors to eukaryotic cells.

i would say it is