Bacteria are one of the tiniest living organisms that can only be seen through a microscope. It is so small that you cannot look with your naked eye.
Some bacteria are wonderful as they can be helpful to human beings in many ways. It is because of the bacteria present in our body that help us to break down carbohydrates and toxins.
Other than that, bacteria perform several other functions necessary for our body.
Not only does the human body has certain types of bacteria, but animals too, and even plants too. So, one can say that every living thing around consists of bacteria in them.
There are more than 30,000 bacteria that are named after human beings, two of which include Aerobic and Anaerobic bacteria.
Key Takeaways
- Aerobic bacteria require oxygen to grow and survive, while anaerobic bacteria can grow and survive without oxygen.
- Aerobic bacteria are commonly found in the environment, soil, water, and living organisms, while anaerobic bacteria are commonly found in sewage, marshes, and the human digestive tract.
- Aerobic bacteria play an essential role in various processes like sewage treatment and food production, while anaerobic bacteria play an important role in processes like fermentation and decomposition.
Aerobic Bacteria vs. Anaerobic Bacteria
Aerobic bacteria require oxygen for their metabolic processes and to produce energy. They use oxygen to break down nutrients and release energy as ATP (adenosine triphosphate). Anaerobic bacteria do not require oxygen to survive and can even be harmed by its presence.

The uses of these two types of bacteria in human and animal cells are different, and because of their basic distinction, they perform differently in the human body.
Comparison Table
Parameters of Comparison | Aerobic Bacteria | Anaerobic Bacteria |
---|---|---|
Oxygen Requirement | Aerobic bacteria need the support of oxygen for their survival. | On the other hand, Anaerobic bacteria do not need oxygen support for their survival. |
Energy Production | As they need oxygen for their survival, they perform the most significant task of providing more energy by breaking down carbohydrates and other nutrients. | Anaerobic bacteria do not provide much energy when compared to aerobic bacteria. |
Final Electron Acceptor | The molecular electron is considered to be the final electron acceptor. | In the case of anaerobic bacteria, the final electron acceptor is carbon dioxide, sulfur, and fumarate. |
Seen | Aerobic bacteria are seen mostly on the surface of a liquid | In the case of anaerobic bacteria, they are settled at the bottom of the liquid. |
Example | Mycobacterium tuberculosis | Clostridium |
What is Aerobic Bacteria?
Aerobic bacteria are bacteria that require oxygen for their survival, and without oxygen, they will die.
There is a huge significance of aerobic bacteria in the human body as well as in animals. With the help of this bacteria, the oxygen gets detoxified with the help of certain enzymes.
Detoxifying oxygen is one of the most important tasks in the human body. While these bacteria do not just purify oxygen but also help break down food molecules so that you can get energy.
Unlike Anaerobic bacteria, this can produce almost double the energy of anaerobic bacteria.
Aerobic bacteria are present in the human gut, where there is less oxygen, and these bacteria get their energy from food sources.
When there is enough oxygen, these bacteria can multiply through a chemical reaction.
Since these bacteria need oxygen for survival, they are mostly seen above a liquid or on the surface of the liquid, unlike anaerobic bacteria below the liquid.
An experiment can be conducted where if you keep these two types of bacteria in a liquid area, you will see that aerobic bacteria will absorb all the oxygen from the air.

What is Anaerobic Bacteria?
Anaerobic bacteria is another type that is just the opposite of aerobic bacteria. Anaerobic bacteria cannot survive when there is a supply of oxygen in a particular area.
In many cases, anaerobic bacteria are found where no oxygen is present in the human body.
Anaerobic bacteria can cause harm where there is no oxygen flow because an injured area with less oxygen-carrying blood flow can cause an infection like tetanus and gangrene caused by anaerobic bacteria.
These bacteria do not detoxify oxygen because they do not need oxygen.
If oxygen is supplied to them, they will die. In Anaerobic bacteria, the final electron acceptor is carbon dioxide, sulfur, and fumarate or ferric.
These bacteria have no oxygen supply at the bottom of the liquid. Anaerobic bacteria provide energy, but compared to aerobic bacteria, they produce much less.
When a runner runs fast and faces a lack of oxygen, anaerobic respiration occurs and produces lactic acid crystals in the muscles.
Because of the creation of lactic crystals, the muscles hurt, and it takes time to heal. Whenever there is a lack of availability of oxygen in human cells or animal cells then, lactic acid is created.

Main Difference Between Aerobic Bacteria and Anaerobic Bacteria
- Aerobic bacteria need the support of oxygen for their survival, whereas anaerobic bacteria do not need the support of oxygen for their survival.
- Aerobic bacteria offer much more energy to the cells than anaerobic bacteria.
- Aerobic respiration help in producing energy with the help of complex processes in the cells.
- Aerobic bacteria are seen mostly on the surface of a liquid, whereas anaerobic bacteria are found below or at the bottom of the liquid.
- An example of aerobic bacteria is Mycobacterium tuberculosis, and an example of anaerobic bacteria is Clostridium.

- https://www.sciencedirect.com/science/article/pii/S0032959299001454
- https://www.acpjournals.org/doi/abs/10.7326/0003-4819-85-4-461
Piyush Yadav has spent the past 25 years working as a physicist in the local community. He is a physicist passionate about making science more accessible to our readers. He holds a BSc in Natural Sciences and Post Graduate Diploma in Environmental Science. You can read more about him on his bio page.