IN CHAPTER 5 WE DISCUSSED plants’ requirements for mineral nutrients and light in order to grow and complete their life cycle. Because living organisms interact with one another and their environment, mineral nutrients cycle through the biosphere. These cycles involve complex interactions, and each cycle is critical in its own right. Because the amount of matter in the biosphere remains constant, energy must be supplied to keep the cycles operational. Otherwise increasing entropy dictates that the flow of matter would ultimately stop. Autotrophic organisms have the ability to convert physical and chemical sources of energy into carbohydrates in the absence.
