They are connected by tendons
The mass is made up of protons and neutrons, the valence electrons only determine stability, not mass
Well, the food is in the environment. I would like to compare it with how bacteriae feed (however my biology is quite rusty), that is, they engulf their food and they "digest" -- not the proper term, since there are no organs to do real digestion -- it.
the radiations that are used to treat cancers are of the gamma type. primarily emitted from cobalt-60 (a radioactive isotope). and it is more controlled than other radiation exposures. i.e. solar radiation which is not controlled.
hope that this helps.
