Which of the following traits is not a characteristic of animals? a- multicellular body structure b- composed of cells with cell walls c- heterotrophic food-getting pattern d- composed of eukaryotic cells 2. which of the following describes the most important difference between invertebrates & vertebrates? a- vertebrates contain multiple tissues, while invertebrates do not b- invertebrates contain multiple tissues, while vertebrates do not c- vertebrates contain a backbone, while invertebrates do not d- invertebrates contain a backbone, while vertebrates do not need !