An enzyme is a special type of protein molecule. intestinal cells produce digestive enzymes that break down food. these enzymes are not produced by blood cells. which statement best explains why? a)the genes for the digestive enzymes are expressed in both intestinal cells and blood cells. b)the genes for the digestive enzymes are not present in the blood cells. c)the genes for digestive enzymes are present in the intestinal cells, but are not expressed. d)the genes for digestive enzymes are not present in the intestinal cells. e)the genes for digestive enzymes are present in the blood cells, but are not expressed