I believer it will be water
Evolution would be the answer you may be looking for.
Specifically, we tested for the presence of lipids, proteins, polysaccharides, and monosaccharides in samples of potato, oil, milk, sugar, egg, rice, tofu, bread, and glucose. It is important to know about the presence of different types of macromolecules in our food because it is important. Google
Passive immunity because animals are passive.
Xylem and phloem are the two tissues that are found within a vein.
Xylem carries water, and phloem carries food, or glucose.