Question

What are the three uses of bacteria?

Answer 1

Bacteria is a single celled microscopic prokaryotic organism. They are considered as a unicellular life form and abundantly found in the earth surface to the digestive tract of humans. The diverse group of bacteria found in the ecosystem may cause disease but many of these are harmless and beneficial to the ecosystem.

Complete answer:
There are many ways the bacteria are beneficial for nature and carry out important functions for the host.
Fixation of nitrogen: The fertility of soil and fixation of nitrogen in soil is carried out by bacterial cells. They are symbiotically associated with the root of the plants and get benefitted both. Plants get their nitrogen, while bacteria get their food from plants. Some bacteria known for nitrogen fixation i.e., Nostoc , Azotobacter.
Preparation of food, chemicals and antibiotics: There are diverse groups of bacteria that have been used in food and chemical industries. Lactic acid bacteria are among the most important group of microorganisms used in fermentation of food such as, Lactobacillus , Lactococcus. Currently most of the antibiotics are produced by bacteria from the genus of Streptomyces.
Degradation of cellulose: Various microorganisms used for degrading cellulose. These species of bacteria secrete cellulase enzymes by some bacteria genera such as Cellulomonas , Pseudomonas , they degrade cellulose which is the component of plant.

Note:
Prokaryotic organisms are very essential for the ecosystem, economy as well as important for recycling the nutrients. Prokaryotic cells are also used in biotechnological applications like water, drug industries. Bacteria are very useful for humans as well as other living organisms.