Such things don't exist in Amerikan society anymore. There's no past experience to anchor a concept with. Nothing better has ever been found. If your jaw ends up pounded into your navel, you've got a good dentist. It worked sufficiently well that the project was cancelled - couldn't take the risk of going to market.
Undergraduates are products of a Liberal public education.
Like all axenic organisms, they are destroyed by contact with the real world. Tell them where carrots come from, and what is commonly applied as fertilizer.