Asample of digestive juice was removed from the stomach of a pig. the juice was placed in a test tube along with some grains of wheat. a second test tube was set up containing an equal number of wheat grains, with distilled water rather than digestive juice. the test tubes were kept for 8 hours at 40 degrees c. after 8 hours the wheat inside the digestive juice had broken into tiny particles. the grains of wheat, in the water, were wet but otherwise unchanged.

Digestive juice is the name for all juices secreted by the organs from the digestive system such as salivary glands, stomach, pancreas and liver. All of them contain enzymes that are responsible for food (macromolecule) break down. Digestive juice from the stomach contains enzyme protease (pepsinogen) which breaks down proteins and stomach acids which is involved in chemical breakdown of food materials. So, that is why the wheat grains are broken into tiny particles.