I think the “junior novels” were written early in development alongside movies, and as such tend to contain material that gets cut or altered, like in “Osmosis Jones” there’s a deleted scene where Ozzy takes Drix to one of Frank’s eyeballs (a theme park called “See World”) to help him realize how much the entire “city” (body) matters to him (this scene was originally set between when Ozzy had to get info on “la muerte roja”, aka “the red death”, which was mentioned by a small germ as the being behind the sore throat early on). Said scene appears as bonus material on the DVD alongside several others.