Popcorn is a type of corn that bursts into irregularly shaped puffs when heated. When heat is applied to a popcorn kernel, pressure builds inside it until the outer hull finally explodes and the gelatinized, starchy interior comes spilling out. This rapidly hardens, becoming the familiar puff. This tasty treat, today a fixture at theater concession stands, is not a modern invention. Evidence suggests humans have been eating it for thousands of years. What are kernels that fail to pop called? Discuss