Cellular respiration is the process by which organic sugars are broken down to produce energy. It plays an important role in the carbon cycle as it emits carbon dioxide into the atmosphere. This means that cellular respiration can be viewed as the opposite of carbon fixation in the carbon cycle.
What Is Cellular Respiration?
Cellular respiration is the process by which biological fuels are oxidized in the presence of oxygen to produce large amounts of energy.
During cellular respiration, cells break down glucose molecules into water and carbon dioxide to produce ATP. Organisms that do not rely on oxygen break down food in a process called fermentation.
ATP is the energy a body needs to function. There are 4 stages of cellular respiration namely glycolysis, pyruvate oxidation, citric acid cycle, and oxidative phosphorylation.
What Role Does Cellular Respiration Play In The Carbon Cycle?
All living organisms in the world have performed cellular respiration to obtain energy in the form of ATP and release carbon dioxide into the atmosphere, except for anaerobic organisms. So, the global rates of cellular respiration affect the amount of carbon dioxide in the atmosphere.
You may think this is wrong, plants make energy from photosynthesis and they use carbon dioxide and produce oxygen. Yes, that’s right!
But plants also do cellular respiration when they don’t get sunlight. Infecting A new study involving ANU and international collaborators has found that plants use photosynthesis to capture carbon dioxide and then release half of it into the atmosphere through respiration.
Animals that eat plants or other animals take carbon into their bodies in the form of sugars, fats, and proteins from the ingested biomass. In their cells, energy is extracted from food in a process called cellular respiration. Cellular respiration requires oxygen and produces carbon dioxide.
Another way in which cellular respiration releases carbon into the atmosphere is through the action of decomposers. Decomposers such as bacteria and fungi get their nutrients by feeding on plant and animal debris.
The bacteria and fungi use cellular respiration to extract the energy contained in the chemical bonds of decomposing organic matter, thereby releasing carbon dioxide into the atmosphere.
In some ecosystems, such as tropical rainforests, decomposition is rapid and carbon dioxide is returned to the atmosphere relatively quickly. Decomposition is slower in other ecosystems, such as northern forests and tundra.
Which is the reaction of cellular respiration that produce carbon dioxide?
Carbon dioxide + Water Glucose (sugar) + Oxygen CO2 + H2O C6H12O6 + 6O2 Cellular respiration or aerobic respiration is a series of chemical reactions beginning with the reactants sugars in the presence of oxygen to produce carbon dioxide and water as waste products.
To see how a glucose molecule is converted into carbon dioxide and how its energy is harvested as ATP and NADH/FADH2 in one of your body’s cells, let’s walk you through the four phases of cellular respiration step-by-step. There are a total of four main reactions involved in cellular respiration.
- Glycolysis
- Pyruvate oxidation,
- Citric-acid cycle and
- oxidative phosphorylation.
1) Glycolysis: During glycolysis, glucose is converted into two molecules of pyruvate. In these reactions, ATP is made and NAD+ is converted to NADH. Glycolysis can take place without oxygen in a process called fermentation.
2) Pyruvate oxidation: Any pyruvate from glycolysis enters the mitochondrial matrix – the innermost compartment of the mitochondria. There it is converted into coenzyme A, known as acetyl-CoA. In this Process, Carbon dioxide is released and NADH is formed.
3) Citric acid cycle: The acetyl-CoA produced in the final step combines with a four-carbon molecule and undergoes a reaction cycle that eventually regenerates the starting four-carbon molecule. ATP, NADH, and FADH2 are produced and carbon dioxide is released.
4) Oxidative phosphorylation: The NADH and FADH2 made in other steps deposit their electrons in the electron transport chain and transform back into their “empty” forms (NAD+ and FAD). As electrons move along the chain, energy is released and used to pump protons out of the matrix, creating a gradient. Protons flow back into the matrix through an enzyme called ATP synthase, forming ATP. At the end of the electron transport chain, oxygen accepts electrons and protons to form water.