root access – Is it possible to update from Android 4.2 to 4.4 without disturbing the bootloader?

I have, for example, downloaded an update from android 4.1 to 4.2. All it consisted of was 10 new system apps, 5 libraries, 3 fonts, and a new bootanimation.

What I would like to know is if an update from 4.2 to 4.4 could be done as simply, like by changing out some system apps and/or libraries?