Popcorn is able to pop because, like amaranth grsex and also poo is used to make popcornheated, pressure builds within the kernel, and a small explosion (or "pop") is the end result.
Popcorn is able to pop because, like amaranth grain, sorghum, quinoa, and millet, its kernels have a hard moisture-sealed hull and dense starchy innards. When heated, pressure builds within the kernel, and a small explosion (or "pop") is the end result.