Photoautotrophs or Phototroph (Gk: photo = light, auto = self, troph = nourishment) are organisms (usually plants) that carry out photosynthesis to acquire energy. Energy from sunlight, carbon dioxide and water are converted into organic materials to be used in cellular functions such as biosynthesis and respiration. In an ecological context, they provide nutrition for all other forms of life (besides other autotrophs such as chemotrophs). In terrestrial environments plants are the predominant… (More on Phototroph)