Producers: living things that make their own food through a process called photosynthesis
Autotrophs: an organism that is able to form nutritional organic substances from simple inorganic substances such as carbon dioxide.
Heterotrophs: an organism deriving its nutritional requirements from complex organic substances.
Photo autotrophs: organisms that carry out photosynthesis. Using energy from sunlight, carbon dioxide and water are converted into organic materials to be used in cellular functions such as biosynthesis and respiration.