Bacteria that make their own food are known as autotrophs or producers, and they do this through the process of photosynthesis or chemosynthesis. Most autotrophs use the process of photosynthesis, which usually involves converting carbon dioxide and water into glucose using the sun?s energy.
These types of autotrophs, called photoautotrophs, use glucose as their source of energy.
In the process of chemosynthesis, autotrophs use energy from inorganic chemical reactions, instead of sunlight to make their own food. Known as chemoautotrophs, they derive energy from inorganic sources, such as ferrous iron, hydrogen sulfide and ammonia to use in chemosynthesis.
These types of autotrophs are rare and live in harsh environments. For example, chemoautotrophs that live close to hydrothermal vents deep below the ocean use hydrogen sulfide and other minerals the vent emits to make their own food through chemosynthesis. Autotrophs found in active volcanoes make their own food by oxidizing sulfur.
Autotrophs are a source food for other organisms. For example, mussels and snails consume bacteria that live close to hydrothermal vents. Other sea creatures such as the octopus consume the mussels and snails. Therefore, autotrophs are an essential part of the food chain, and a decrease in their numbers can affect the numbers of the organisms that feed on them.