Daniel Booth, age 7, of Decota, West Virginia, for his question:

What exactly is a chicken's gizzard?

The chicken's gizzard is a firm little fist that helps to digest her food. She has no teeth with which to chew and so she must swallow each bite in a whole gob. Her tummy cannot digest whole gobs of food and the lumps must be mashed and bashed to soft pulp. Most of this work is done by the gizzard. This tough little fist is very hard and strong but it has no bones. It is really a very strong muscle.

When the gizzard is full of chicken food, it grinds and squeezes, pinches and twists. But chicken food is often seeds and seeds are hard. The gizzard needs a little extra help to grind them to mushy pulp. So the chicken swallows a few gritty pebbles along with her snacks of grain. They go down with her food in the grinding gizzard. Their jagged edges slice and tear up the food and help the tough little fist to mash it to pulp.