Pfhor breathe oxygen? Why do they always go around with masks on? Any theories on what the atmosphere was in Acme Station/Post Naval Trauma?
: Our blood is red because the iron in our hemoglobin is what lets it bind
: oxygen, and oxydized iron (rust) is red.
: I've always figured green-blooded aliens who breath the same atmosphere as us
: probably have a copper-based hemoglobin-equivalent, as copper oxydizes
: green (see the statue of liberty).
: AFAIK carbon dioxide is fairly inert, and plants only "breath" it
: in the sense that they use solar energy to rip the carbon out of it to
: build their cells with. (The leftover oxygen is a toxic by-product. We
: animals do the opposite process, oxydizing organic carbon compounds to
: release the stored energy from them). It wouldn't really work the same way
: as oxygen in as far as coloring some hypothetical CO2-breathing alien
: animal's blood.