very good paper…it was interesting and kept my focus. Be careful with grammar and wording though.
First paragraph under CF… say "it has been proposed" instead of it is possible"
when you talk about salt concentrations, you say "before the sweat chloride test….unknown reasons, of CF" this is awkwardly worded. the next paragraph you say "however, in indiiduals…it should be moving, as well" there is a subject/verb disagreement.
In your conclusion, I would refrain from using "I don't think" or "I believe." you can still voice your opinion about it using other words.
Overall, good paper