Resizing Matter: Part 4

A living creature exchanges chemical matter with its surroundings. Two necessary input streams: oxygen and foodstuff (including water). You could go without food for some time, without water for less time, but you’d expire rather quickly without oxygen to inspire. If a resized creature has all atoms resized proportionally, this might cause a problem utilizing breathed-in oxygen.

Let’s assume you’ve engorgio-ed yourself into a giant, perhaps to intimidate a foe. You’d still need incoming oxygen to drive your body’s metabolism and keep you alive. Oxygen is carried through your bloodstream by hemoglobin. The key interaction is a chemical bond between the O₂ molecule and an iron center in a porphyrin ring. (See figure below from The Chemistry of Hemoglobin and Myoglobin.) 

The magically enlarged molecules and pathways in your body ‘see’ the incoming O₂ molecules as smaller than usual. Their lower mass (see Part 1 and Part 2 of this series) will result in speedier diffusion through the relevant channels. The O₂ would likely bind to hemoglobin, perhaps with a slightly stronger bond, that might result in slightly slower release. More of a problem, the O₂ might bind to other molecules it normally doesn’t interact with because its smaller relative size allows it to sneak into crevices and react chemically due to its biradical nature. But perhaps hemoglobin as a carrier is less important, if O₂ can diffuse its way through to its targets. Collateral damage is the bigger problem here.

If you’ve reducio-ed yourself for Ant-Man purposes, now the relatively larger O₂ might not be able to bind to hemoglobin at all. It’s diffusion capabilities are also probably reduced, although at least it might not cause as much collateral damage along the way.

The solution to this conundrum is for the O₂ molecules to resize as they enter your body. Perhaps the effect of a engorgio or reducio spell is to generate some sort of field where anything that enters the field (defined by the boundary of you?) resizes in the same way. Ant-Man’s suit might work this way. A breathing filter automatically resizes any molecule that enters. Exhaled molecules (e.g. CO₂) aren’t a concern although I would expect they would resize in the opposite way as they leave the filter out to the environment.

This complication of your body’s metabolism needing constant input streams suggests that engorgio and reducio are particularly difficult magical spells to cast, especially on living organisms if you don’t want them to die within minutes. Even if cast successfully, these spells are likely to be temporary. Even if the O₂ intake problem was ‘solved’, there are other interactions between the creature and its environment that are likely to be problematic. Biochemistry. It’s beautiful and complicated. All the more reason to learn its details if you wanted to be a magical practitioner of the highest order!