4. Corn kernels have an outer endosperm and an inner endosperm. A purple outer endosperm is dominant to a colorless (clear) outer endosperm. A yellow inner endosperm is dominant to a white inner endosperm. The inner endosperm color is not seen if the outer endosperm color is the dominant form. If the outer color is recessive or suppressed, the inner color is visible. In addition, the purple outer endosperm gene is suppressed and not expressed when a dominant color suppressor gene is present.