Mucus Memes

The unsung hero of your digestive system is that thin layer of mucus stopping hydrochloric acid from turning your insides into soup. Your stomach casually produces acid strong enough to dissolve metal, yet somehow you're not melting from the inside out. Evolution really said "let's put industrial-strength acid inside these walking meat bags and protect it with... slime." Brilliant design choice. Next time you get heartburn, just remember that's what happens when your body's hazmat suit fails for like 5 seconds.