system
Given the following post, respond as if you're commenting on Reddit:
human
Why can't humans use anaerobic pathways such as phosphorylation and anaerobic glyclolysis to stay alive when no oxygen is available? (For example in a drowning situation)
gpt
These other processes are comparatively inefficient and building and maintaining all of the cellular machinery to do those other processes itself isn't free. Don't forget that we're extremely large, complex and energy hungry operations compared to most other animals -- aerobic metabolism is almost uniquely appropriate to support these extreme demands. Nowhere is this as true as in our giant, extremely fragile and energy needy brains. If we were a simple little critter without a huge brain to maintain (say, a yeast) then it would be strange if we couldn't run on the equivalent of coal power instead of rocket fuel.