The shirt reads: “ATP LOW” above and “PLEASE INSERT LUNCH” on the plate beneath.
In the middle, a droopy cartoon brain sags over a fuel gauge whose needle is pinned to E, with three small ATP markers along the dial.
ATP is the molecule cells actually run on, so the fuel gauge is not a metaphor so much as a simplification. The brain has clearly been running on empty since about eleven.
For biology students, for the afternoon slump, and for anyone who needs to be fed before they can be reasoned with.
