What is an autotrophic bacteriumSolutionAutotrophic Bacteria

What is an autotrophic bacterium?

Solution

Autotrophic Bacteria:

Autotrophic bacteria are prokaryotic unicellular organisms of kingdom monera.

Autotrophic bacteria use inorganic substances to make energy in the form of organic matter. Two major types are photoautotrophs and chemoautotrophs.

Photoautotrophs obtain energy from sunlight and convert it into chemical energy. Few phototrophic bacteria also have pigments (lamellae) known as cyanobacteria. The bacterial photosynthesis is different from that of green plants. Unlike plants oxygen is not released. It is known as anoxygenic photosynthesis. These bacterial species are useful to remove harmful carbon dioxide from the atmosphere. The following reaction occurs in presence of light

CO₂ +H₂S ---------------------------.> Sugars + sulphur + water

Chemoautotrophs use chemical energy. Chemoautotrophs take inorganic raw material and get energy by oxidation of inorganic substances. The major energy sources for bacteria are carbohydrates and sugars. Nitrifying bacteria, sulphur bacteria, iron bacteria etc.