Maria and sam are studying about cells, tissues, organs, and organ systems in the human body. this is a picture of the human digestive system. each part is a different color. each part does something different during the process of digestion. even though each part of the digestive system is different, each part is also alike. what is one thing that each part shares with the others? a) each part contains organs. b) each part of the system is made of cells. c) each part breaks down food into smaller pieces. d) each part of the digestive system is made of exactly the same cells.