Oh no, it definitely does.

You know how when you hold your breath for a long time, your lungs start to burn? That must be because of lack of oxygen right? Your body telling you that you need oxygen!

No. Your lungs don’t give a shit about oxygen. Your lungs start to burn because of a build up of carbon dioxide. When you breathe in and out your lungs absorb some oxygen for your body and release some carbon dioxide, but it’s not 100% efficiency for a breath. So when your hold your breath for a while your lungs build up CO2 and eventually start to burn.

That’s it. That’s what your lungs do. They sense CO2.

Sure, if there’s an irritant in the air, something that directly irritates mucous membranes like ammonia or tear gas or whatever, that burns, it hurts.

But your lungs don’t give one fat shit or another whether they’ve got oxygen or not. Just carbon dioxide.

Carbon monoxide? Super poisonous gas? Nope. Not a problem as far as your lungs are concerned. Breathe that in all day long without a single alarm bell sent to the brain. That’s how “Weird Al’s” parents died. That’s how LOTS of people die.

What about an area full of gasses that are neither carbon dioxide nor oxygen, like straight nitrogen? Your lungs will breathe happily away until you pass out and die.

That last bit? That’s how a SCUBA rebreather can fail and divers die without even really knowing there’s a problem.

It’s also gaining traction as a humane way to execute prisoners (nitrogen especially). Because the condemned don’t feel a thing and it’s super fatal (better kill chance than lethal injection). They breathe and breathe and get a little giddy and then they fall unconscious and then they die. No pain, not even a panic reaction.

And their dick-bag lungs don’t give a shit the whole time. They just happily chug away.

That’s just the lungs, that’s just off the top of my head. The knees have some design flaws, core parts of the spine are completely unrepairable, and the prostate is a fucking death trap. Again, all off the top of my head.

It might be cool to think we’re just a sack of grey goo piloting a robot of calcium and meat, but it’s kind of a mediocre robot and it’s really not great meat.