Grains are a significant source of carbohydrates. In nature, grains are composed of three main parts. When all three parts of the grain are present in their original proportion, it is considered a whole grain. Identify the three parts of grain on the kernel of wheat. Macmillan Learning Answer Bank germ endosperm Now, match each part to its corresponding description. Part C bran bran Description contains the highest amount of starch and protein embryo of the seed; contains essential fatty acids, and a number of B vitamins and minerals contains the majority of dietary fiber, as well as B vitamins and minerals Answer Bank germ endosperm