a cell adapts using natural celection in the long term
in the short term, look at this Wikipedia article.
https://en.wikipedia.org/wiki/Cellular_adaptation
 
        
                    
             
        
        
        
Answer:
they were a paracite 
Explanation:
the mitochondrial theorem or something. basically they live in a symbiotic relationship but originally it was two separate life forms. this is true for the mitochondria and chloroplasts