The organisms at the bottom of the food chain are usually called producers. These are living things like plants, algae, and some bacteria that can make their own food using sunlight, water, and carbon dioxide. This process is called photosynthesis.They are important because they are the first source of energy in the food chain. All other organisms, like herbivores (plant-eaters), carnivores (meat-eaters), and omnivores (both plant- and meat-eaters), depend on producers either directly or indirectly for food.Examples of producers:GrassTreesAlgae in pondsPhytoplankton in oceans