When organisms breathe, they are exchanging gases between their body cells and the surrounding environment, a process known as respiration. All living organisms, from plants and animals to prokaryotic bacteria, archaeans, eukaryotic protists, fungi, and animals, are capable of respiration. A reaction between glucose and oxygen occurs during normal human respiration, resulting in the production of the energy required for growth, repair, and movement. Water and carbon dioxide are byproducts of respiration that must be excreted for the body to function properly.
Respiration can be defined as a metabolic biochemical process that occurs in all living cells of an organism and is characterised by the production of energy through the intake of oxygen and the release of carbon dioxide as a result of the oxidation of a variety of organic compounds. The Adenosine-triphosphate (ATP) molecule, also known as the energy molecule, is responsible for the production of the generated energy.
The various types of respiration include:
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Aerobic respiration
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Respiration in anaerobic conditions
Aerobic respiration
In the presence of oxygen, it is a type of cellular respiration that takes place and results in the production of energy. This type of respiration can be observed in both plants and animals, and the end products of this type of respiration are water and CO2.
Glucose (C6H12O6) + Oxygen 6(O2) = Carbon dioxide 6(CO2) + Water 6(H2O) = Energy (ATP)
This type of respiration occurs when glucose molecules are split in the presence of oxygen, and the end products or by-products that are released are carbon dioxide (CO2), water, and energy in the form of ATP, as observed. 2900 kilojoules of total energy are released during this reaction, which is used to produce the ATP molecules that are produced. It can be found in all types of multicellular organisms, including humans.
Anaerobic respiration
Respiration in anaerobic conditions
Anaerobic respiration is a type of cellular respiration that occurs in the absence of oxygen and results in the production of energy in the cell. During this process, glucose is broken down without the assistance of oxygen, and the by-products produced are alcohol, carbon dioxide (CO2), and energy, also known as ATP. It is the cytoplasm of a cell that is responsible for the process.
The following is the chemical reaction that occurs during this process:
Glucose (C6H12O6) decomposes into alcohol 2(C2H5OH) and carbon dioxide 2(CO2), releasing energy (ATP). Lactic Acid Fermentation and Anaerobic Respiration are two types of anaerobic respiration.
Fermentation in the presence of alcohol
In anaerobic fermentation, glucose is split in the absence of oxygen to produce two molecules of lactic acid and two molecules of ATP. Lactic acid fermentation is one of several types of anaerobic fermentation.
One or more of the three elements of the process of respiration may be referred to as respiration. For starters, the term “respiration” can refer to either external respiration or the process of gas exchange between the air and the cells of an organism. Second, respiration can refer to internal respiration, which is characterised by a gas exchange between the blood and the cells of the body (also known as cellular respiration). In contrast to anaerobic respiration, aerobic respiration is cellular respiration that does not require the presence of oxygen.
The Various Stages of Respiration
The process of cellular respiration is carried out by a variety of metabolic pathways. The breakdown of glucose results in the formation of water, carbon dioxide, and a small amount of ATP. The production of even more ATP occurs later in the process, which is known as oxidative phosphorylation, which is powered by electron transport through the electron transport chain. The following is a brief overview of the various stages of cellular respiration:
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Glycolysis is a chemical transformation in which glucose, a six-carbon sugar, goes through several chemical transformations. Pyruvate and a three-carbon organic molecule are produced as a result of this reaction. Additionally, two molecules of ATP and NADH are produced.
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In the process of pyruvate oxidation, each pyruvate molecule enters the mitochondrial matrix and is converted to a two-carbon molecule that is bound to Coenzyme A. Acetyl CoA is the name given to the entire compound. As a result of this reaction, carbon dioxide and NADH are produced as byproducts.
- When the Acetyl CoA combines with a four-carbon molecule, a series of chemical reactions take place that is collectively referred to as the Citric Acid Cycle (also known as the Krebs cycle) are triggered. Finally, the four-carbon starting molecule is regenerated with the addition of FADH2, NADH, carbon dioxide, and two molecules of ATP to complete the cycle. The Krebs cycle is also referred to as the tricarboxylic acid cycle in some circles.
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Oxidative Phosphorylation is a process in which the FADH2 and NADH produced in the Krebs cycle donate their electrons to oxygen through various electron carriers in the electron transport chain, resulting in the formation of oxidative phosphorylation. Specifically, the mitochondrial matrix is where the reaction takes place. It forms a gradient as electrons move down the chain, releasing energy that is then used to pump protons out of the matrix as the electrons move further down. The protons then flow back into the matrix with the assistance of the enzyme ATP synthase, which produces the energy molecule ATP. To complete the chain, oxygen accepts the electrons and protons, resulting in the formation of water.
The final result is that one molecule of glucose results in the production of 38 molecules of ATP. It should be noted that glycolysis can also take place in the absence of oxygen, and this is referred to as fermentation in the scientific community.
Conclusion
Respiration can be defined as a metabolic biochemical process that occurs in all living cells of an organism and is characterised by the production of energy through the intake of oxygen and the release of carbon dioxide as a result of the oxidation of a variety of organic compounds. In the presence of oxygen, it is a type of cellular respiration that takes place and results in the production of energy.
Anaerobic respiration is a type of cellular respiration that occurs in the absence of oxygen and results in the production of energy in the cell. The process of cellular respiration is carried out by a variety of metabolic pathways. The breakdown of glucose results in the formation of water, carbon dioxide, and a small amount of ATP. The production of even more ATP occurs later in the process, which is known as oxidative phosphorylation, which is powered by electron transport through the electron transport chain.