Jennifer Lyngstad, age 8, of Norristown, Penn., for her question:

WHAT MAKES POPCORN POP?

Popcorn is a special type of corn with small, hard kernels. Under heat, the kernels will explode into tasty white food.

The special kernels burst when they contain 13.5 percent moisture and heat reaches 400 degrees Fahrenheit. When heated, the moisture changes into steam. The hard coverings keep the steam from escaping, causing pressure to build up inside the kernel.

The pressure finally bursts the kernel.

Good popcorn kernels expand from 30 to 35 times their size when popped.

Farmers grow popcorn in much the same way as field corn. But rows of popcorn are planted much closer together. The ears are carefully harvested after they have matured and dried.

Most United States commercial popcorn is grown in Indiana, Iowa, Nebraska and Ohio.