In order for plants to make their own food, they must go through a process called photosynthesis. This process occurs in the chloroplasts of a cell. To begin this process, all items needed must go to the cells of a plant. Water and nutrient are absorbed from the soil through the roots. A tube called the xylem carries only water up the stem to the rest of the plant. Gas exchange in the plants occur in the tiny pores of a leaf called the stomata. This is opened and closed by the guard cells. The food produced by this process is called ATP and it is a macromolecule known as a nucleic acid.
