It is vital for every living organism to derive and make use of energy for survival. This energy is obtained by breaking down sugars and then hoarding them in ATP. Consequently, ATP plays a crucial role in storing and transferring energy in cells.
There are two major processes that lead to the formation of ATP. These include cellular respiration and fermentation.
Cellular Respiration vs Fermentation
The main difference between cellular respiration and fermentation is that in the process of cellular respiration, glucose is fully oxidized into carbon dioxide and water whereas the process of fermentation oxidizes glucose only partially while producing small organic molecules as waste. This means that cellular respiration discharges more energy than fermentation.
Cellular respiration is a survival process that takes place inside the cells of living organisms. Through its action, chemical energy derived from nutrients and oxygen molecules is converted into ATP. Along with the production of ATP, a certain amount of waste is also released. This fuels all the cellular activities that take place inside the body.
Fermentation is another process by which ATP is produced. However, fermentation is not as efficient as the former because it does not oxidize glucose fully. This means that only a little ATP is created from chemical energy along with a larger amount of waste products. This waste includes lactic acid and ethanol.
Comparison Table Between Cellular Respiration and Fermentation
| Parameters of Comparison | Cellular Respiration | Fermentation |
| Oxidization | Cellular respiration fully oxidizes glucose to produce ATP. | Fermentation only oxidizes glucose partially, resulting in larger waste production. |
| Occurrence | Cellular respiration occurs in the cytoplasm as well as mitochondria. | Fermentation occurs only in the cytoplasm. |
| Production | Through cellular respiration, around 36 ATPs are produced. | The process of fermentation only produces 2 ATPs. |
| Water | As a result of cellular respiration, water is produced as a by-product along with ATPs. | No water is produced during the process of fermentation in the cells. |
| Types | Cellular respiration is of two types – Aerobic respiration and anaerobic respiration. | The process of fermentation can take place in two ways – Ethanol fermentation and lactic acid fermentation. |
| Organism | Cellular respiration takes place in higher organisms. | Fermentation takes place in microorganisms such as yeast. |
What is Cellular Respiration?
Cellular respiration is the process through which glucose is oxidized to form chemical energy, which is then converted into ATPs. Along with ATPs, lactic acid and ethanol are discharged as by-products. This process takes place in higher organisms such as human beings and other animals. The process is crucial for survival as it fuels the cellular activity in the body, which allows a living organism to function.
Generally, plant and animal cells use nutrients such as sugar, amino acids, and fatty acids in the process of cellular respiration. Meanwhile, oxygen (O2) is most used as the oxidizing agent that leads to the discharge of chemical energy. This chemical energy is then stored in the ATP which is the principal molecule for storing and transferring energy at a cellular level. This energy can be used to carry out other processes such as biosynthesis, locomotion and much more.
Cellular respiration is of two types – Aerobic respiration and Anaerobic respiration. Aerobic respiration is the process in which oxygen plays a vital role in creating ATPs. On the other hand, Anaerobic respiration does not require the use of oxygen. Such a process take place in organism found in unusual or rare places such as underwater caves or near hydrothermal vents.
What is Fermentation?
Fermentation is another process by which ATPs are produced in living beings. However, this process takes place only in microorganisms such as yeast. Fermentation oxidizes glucose partially to form ATPs which leads to a high amount of waste production. Unlike cellular respiration, the process of fermentation is slow and not as efficient as only 2 ATPs are produced each time.
The process of fermentation takes place when there is a lack of oxygen intake in the cell. In such a case, pyruvic acid is not metabolized by cellular respiration, but by fermentation. The pyruvic acid remains only in the cytoplasm, unlike cellular respiration, which also transports pyruvate to the mitochondria. In the cytoplasm, the pyruvate gets converted into waste products that may or may not be discharged from the cells.
There are two types of fermentation processes that take place in microorganisms. These include ethanol fermentation and lactic acid fermentation. Fermentation oxidizes NADH to convert it into NAD+, which is then reused in glycolysis. When the waste products during the process turn out to be ethanol and carbon dioxide, ethanol fermentation has taken place. Similarly, when the waste product is lactic acid, such as in the case of skeletal muscles, lactic acid fermentation has taken place.
Main Differences Between Cellular Respiration and Fermentation
- Cellular respiration fully oxidizes glucose to produce ATP while fermentation only oxidizes glucose partially.
- Cellular respiration occurs in the cytoplasm as well as mitochondria while fermentation occurs only in the cytoplasm.
- Cellular respiration generates around 36 ATPs while fermentation only generates 2 ATPs.
- Cellular respiration produces water as a by-product while fermentation does not produce water.
- Cellular respiration takes place in higher organisms while fermentation takes place only in microorganisms such as yeast.
- Oxygen is crucial in the process of cellular respiration whereas fermentation does not require oxygen.
Conclusion
Cellular respiration and fermentation are two processes that lead to the formation of ATPs in living organisms. However, while cellular respiration takes place in higher organisms, fermentation takes place only in microorganisms. This can be a useful explanation for why cellular respiration generates ATPs faster and on a larger scale than fermentation does.
A major difference between the two is that cellular respiration oxidizes glucose fully while fermentation only oxidizes glucose partially. As a consequence, the type and amount of waste products that are discharged also differ. Another major difference between them is that cellular respiration takes place in the cytoplasm as well as the mitochondria while fermentation only takes place in the cytoplasm.
References
- https://onlinelibrary.wiley.com/doi/abs/10.1002/tea.3660310605
- https://academic.oup.com/plphys/article-abstract/79/3/879/6081495