{"messageId": "1961", "unrefinedText": "the endosymbiotic theory proposes that several key organelles of eukaryotic cells especialy mitochondria and chloroplasts evolved from certain prokaryotes"}
{"messageId": "1961", "refinedText": "The endosymbiotic theory proposes that several key organelles of eukaryotic cells, especially mitochondria and chloroplasts, evolved from certain prokaryotes."}