Why Did Everyone Draw that Fancy "S" in Grade School

"The reason kids go through this is probably because it's a Moebius strip," he said, referring to the sort of looped one-surface shapes Escher was fond of drawing. "It can't be drawn continuously, but it does have a perpetual flow." I think he was on to something. Most nine-year-olds can't draw, so when someone hands them a magical recipe to create something fairly cool, on demand—that'll go viral. Especially when the shape has the sophisticated, mathematical lineage of a Moebius strip. Y...

 Human Respiration is Carbon Neutral

The very first time you learned about carbon dioxide was probably in grade school: We breathe in oxygen and breathe out carbon dioxide. Any eight-year-old can rattle off this fact. More specifically, the mitochondria within our cells perform cellular respiration: they burn carbohydrates (in the example shown below, glucose) in the oxygen that we breathe in to yield carbon dioxide and water, which we exhale as waste products, as well as energy, which is required to maintain...