Everyday Science: Wheat Quiz

Historians think humans have cultivated wheat for about 10,000 years, though archeologists have discovered evidence of milling operations that date back even further.

Wheat dominates an estimated 500 million acres worldwide -- more than any other food crop.

Roughly 10 percent goes right back into the ground to ensure future harvests, but most of the rest goes to feed humans and livestock around the world.

The wheat plant's life cycle takes place in four stages: tillering, stem extension, heading and ripening.

Each grain or kernel of wheat consists of a wheat plant embryo called a germ (as in germinate), protected by a thick outer coating called the bran and fueled by the protein-rich endosperm.

Triticum aestivum is known as "common wheat." We use this variety in flour and bread making.

A subspecies of common wheat, Triticum compactum, or "club wheat," produces a softer flour and is mostly used in cakes, cookies and crackers.

Threshing is the act of removing the wheat grains from the rest of the head or chaff.

The germ contains fat, which can turn rancid in flour if not properly stored.

In white bread and bleached white flour, both the bran and the endosperm have been removed to ensure smoother texture and longevity.