This program looks as two naturally occurring phenomena that are essential to the survival of plants, light and water. It covers photosynthesis and cellular respiration, and compares the products and reactants, and other characteristics of each process. The vital role of water in plants is explored, including the movement of water into a plant through its roots, transportation and translocation of water and nutrients inside a plant, and the ultimate release of water vapour into the atmosphere, or transpiration. It explains the function of vascular tissues, or xylem and phloem, and their importance in moving various substances around a plant. The junior program covers the material at a more general and simplistic level, which is suitable for lower/middle secondary levels. The senior program covers the material in more complex terms, and is pitched at students of senior biology.