Little heard of here in the west is the interesting area of Kaiju-biology (Kaiju means monster). To see the sort of thing that kaiju-biologists get up to, go here (please do, you won't regret it). It is said on some Godzilla websites (here for example) that Kenichi Yamane wrote a thesis on Godzilla's biology, focusing in particular on Godzilla's eventual demise (in the 1999 film Godzilla vs. Destoroyah) by way of radioactive meltdown. The cutaway pictures above and near the top are - apparently - taken from this thesis. It might not surprise you, however, to find that Yamane is not a real scientist, but one of the main characters of Godzilla vs. Destoroyah. In fact, Yamane is the adopted grandson of the Dr Yamane from the original Godzilla movie of 1954.
How does Godzilla generate radioactivity? Apparently its stomach has mutated into a new organ: the plasma gland [I've always argued for the plasma gland -- the Editor]. Radioactive particles rise from here to be expelled via the mouth during combat, and excess radioactivity is also passed into the dorsal scutes at the same time 'not unlike the overflow guard in your ordinary bathtub', apparently (according to here: this is where the adjacent image comes from). Thanks to its plasma gland, Godzilla continually generates new radioactivity as a source of power, discharging the excess via the scutes and a duct leading to the mouth. This also means that Godzilla doesn't need to eat, and that must be a good thing when you weigh over 24,000 tons. There are other speculations on Godzilla's biology, including on cell structure, and on the mysterious substance known as Regenerator G-1 and allowing him unparalleled regenerative abilities.
Find this topic fascinating? You need to check out movie physics.
Conversely, if you find today's posts tedious... well - it's not like you're paying me for the content.