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Anaerobic Respiration

Anaerobic Respiration

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Welcome to our article about anaerobic respiration! This process is used by organisms when they don't have access to oxygen but still need energy for their metabolic processes. In this article, we will explore the definition, formula, and differences between aerobic and anaerobic respiration.

Aerobic respiration is the process by which oxygen and ATP break down glucose, which we covered in a previous article. However, when there is no oxygen, anaerobic respiration comes into play.

Anaerobic respiration occurs in the cytoplasm of the cell and involves two stages: glycolysis and fermentation. It is a distinct process from aerobic respiration. During anaerobic respiration, ATP breaks down glucose to form either lactate (in animals) or ethanol (in plants and microorganisms).

If you've ever done an intense workout, you may have experienced muscle soreness the next day. Until recently, it was believed that lactic acid produced during anaerobic respiration was to blame for this soreness. However, recent research suggests that stiff muscles are due to various physiological effects in response to the trauma suffered by muscles during exercise. Nowadays, the theory is that lactic acid is a valuable fuel for your muscles, not an inhibitor!

So, there you have it - anaerobic respiration in a nutshell. We hope you found this article informative interesting, anapiration is process for organisms when oxygen is not available for energy production.

 

The cytoplasm of plant and animal cells
The cytoplasm of plant and animal cells

What is the difference between aerobic and anaerobic respiration?

In our previous article, we explored the differences between aerobic and anaerobic respiration in detail. If you don't have much time, here's a quick summary:

Aerobic respiration happens in both the cytoplasm and mitochondria, while anaerobic respiration only occurs in the cytoplasm. Aerobic respiration requires oxygen, but anaerobic respiration doesn't. Overall, anaerobic respiration produces less ATP than aerobic respiration. The main products of anaerobic respiration are carbon dioxide and ethanol (in plants and microorganisms) or lactate (in animals), while the main products of aerobic respiration are carbon dioxide and water.

Despite their differences, both processes have some similarities, including the production of ATP to power important metabolic processes and the breakdown of glucose through oxidation during glycolysis.

What are the stages of anaerobic respiration?

Anaerobic respiration has only two stages, and both occur in the cell's cytoplasm.

Table 1 should help you recognise the symbols used in the chemical formulas. You might notice some formulas contain numbers before the substance. The numbers balance chemical equations (no atoms are lost during the process).

Summary of the chemical symbols
Summary of the chemical symbols

Glycolysis

C6H12O6 + 2 ADP 2 Pi + 2 NAD+ → 2 Pyruvate ATP + 2 H+ + 2 H2O

Glycolysis is the same whether respiration is aerobic or anaerobic. Glycolysis occurs in the cytoplasm and involves splitting a single, 6-carbon glucose molecule into two 3-carbon pyruvate molecules. During glycolysis, several smaller, enzyme-controlled reactions occur in four stages: phosphorylation, creation of triose phosphate, oxidation, and ATP production.

In the phosphorylation stage, two ATP molecules are split into two ADP molecules and two inorganic phosphate molecules (Pi) via hydrolysis, which uses water to split ATP. This process provides the energy needed to activate the glucose and lowers the activation energy for the following- reaction.

In the creation of triose phosphate stage, each glucose molecule (with the two Pi groups added) splits in two to form two triose phosphate molecules, a 3-carbon molecule.

In the oxidation stage, hydrogen is removed from the two triose phosphate molecules and transferred to NAD+, a hydrogen-carrier molecule, producing reduced NAD (NADH).

In the ATP production stage, the two newly oxid triose phosphate molecules convert into another 3-carbon molecule known as pyruvate. This process also regenerates two ATP molecules from two molecules of ADP.

Fermentation

Fer two different products depending on the organism respiration anaerobically. Lactic acid fermentation occurs in humans and animals. The process involves pyruvate donating an electron from an NADH molecule, oxidizing NADH and converting it to NAD+. Lactic acid forms as a by-product. Lactate is a deprotonated form of lactic acid. Ethanol fermentation occurs when bacteria and other microorganisms respire anaerobically. The process involves a carbox group being removed from pyruvate, releasing carbon dioxide. A 2-carbon molecule called acetaldehyde forms. NADH is reduced and donates an electron to acetaldehyde, forming NAD+. The donated electron and H+ ion allow the formation of ethanol from acetaldehyde.

The following diagrams illustrate the entire process oferobic respiration in animals and bacteria/microorganisms, respectively: 

The steps of anaerobic respiration in animals
The steps of anaerobic respiration in animals

Lactic dehydrogenase helps speed up (catalyse) the reaction for lactic acid fermentation, while pyruvate decarboxylase and aldehyde dehydrogenase are the two enzymes that help catalyse ethanol fermentation.

What is the anaerobic respiration equation?

The overall equation for anaerobic respiration in animals is: glucose → 2 lactate + 2 ATP + 2 H2O

The overall equation for anaerobic respiration in plants or fungi is: glucose → 2 ethanol + 2 carbon dioxide + 2 + 2 H2O

Anaerobic respiration is a type of respiration that does not require oxygen and can occur in animals, plants, and other microorganisms. It only occurs in the cytoplasm of the cell. Anaerobic respiration has two stages: glycolysis and fermentation. Glycolysis in anaerobic respiration is similar to that in aerobic respiration, where a 6-carbon glucose molecule splits into two 3-carbon pyruvate molecules. Fermentation then occurs following glycolysis. Pyruvate is converted into either lactate (in animals) or ethanol and carbon dioxide (in plants or fungi). A tiny amount of ATP forms as a by-product.

Anaerobic Respiration

Does anaerobic respiration require oxygen?

Only aerobic respiration requires oxygen, whilst anaerobic respiration does not. Anaerobic respiration can only occur without oxygen, altering how glucose breaks down into energy.

How does anaerobic respiration occur?

Anaerobic respiration does not require oxygen but only occurs when oxygen is absent. It only takes place in the cytoplasm. The products of anaerobic respiration differ in animals and plants. Anaerobic respiration in animals produces lactate, whereas ethanol and carbon dioxide in plants or fungi. Only a small amount of ATP forms during anaerobic respiration. Anaerobic respiration only has two stages: Glycolysis in anaerobic respiration is similar to that in aerobic respiration. A 6-carbon glucose molecule of the glucose still splits into two 3-carbon pyruvate molecules. Fermentation then occurs following glycolysis. Pyruvate is converted into either lactate (in animals) or ethanol and carbon dioxide (in plants or fungi). A tiny amount of ATP forms as a by-product. 

What is anaerobic respiration?

Anaerobic respiration is how glucose breaks down in the absence of oxygen. When organisms respire anaerobically, they produce ATP molecules through fermentation, which can produce lactate in animals, or ethanol and carbon dioxide in plants and microorganisms.

What is the difference between aerobic and anaerobic respiration?

The main differences between aerobic and anaerobic respiration are listed below:Aerobic respiration occurs in the cytoplasm and the mitochondria, whilst anaerobic respiration only occurs in the cytoplasm.Aerobic respiration requires oxygen to take place, whilst anaerobic respiration does not. Anaerobic respiration produces less ATP overall than aerobic respiration.Anaerobic respiration produces carbon dioxide and ethanol (in plants and microorganisms) or lactate (in animals), whilst the main products of aerobic respiration are carbon dioxide and water.

What are the products of anaerobic respiration?

The products of anaerobic respiration vary depending on what kind of organism is respiring. The products are ethanol and carbon dioxide (in plants and microorganisms) or lactate (in animals).

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