Why aerobic respiration is important




















This is a less efficient method of energy release than aerobic respiration because oxygen is involved in a key, energy releasing step in the process of respiration. When this step cannot occur such as when there is limited oxygen an alternate pathway is taken which leads to a small amount of energy being released along with in the case of humans and non-human animals lactic acid.

What is aerobic respiration and why is it important in the human body? Answered by Harriet L. Need help with Biology? Autotrophic organisms, namely plants, algae, and photosynthetic and chemosynthetic bacteria, convert inorganic materials into such biomolecules by harnessing energy from the environment, such as from sunlight during photosynthesis.

Heterotrophic organisms are unable to synthesize high-energy biomolecules from inorganic materials, so they obtain energy by consuming carbon compounds produced by other organisms, primarily from autotrophs. When energy is needed, chemical bonds of carbon compounds are broken to harvest the energy stored in these bonds. The processes to harvest energy from biomolecules are called cellular respiration. Cellular respiration occurs in both autotrophic and heterotrophic organisms, where energy becomes available to the organism most commonly through the conversion of adenosine diphosphate ADP to adenosine triphosphate ATP.

There are two main types of cellular respiration—aerobic respiration and anaerobic respiration. Aerobic respiration is a specific type of cellular respiration, in which oxygen O 2 is required to create ATP. In this case, glucose C 6 H 12 O 6 can be oxidized completely in a series of enzymatic reactions to produce carbon dioxide CO 2 and water H 2 O.

Aerobic respiration occurs in three stages. A process called glycolysis splits glucose into two three-carbon molecules called pyruvate. This process releases energy, some of which is transferred to ATP.

Next, pyruvate molecules enter the mitochondria to take part in a series of reactions called the Krebs cycle, also known as the citric acid cycle. This completes the breakdown of glucose, harvesting some of the energy into ATP and transferring electrons onto carrier molecules.

In the last stage, known as oxidative phosphorylation, electrons pass through an electron transport system in the mitochondrial inner membrane, which maintains a gradient of hydrogen ions. Cells harness the energy of this proton gradient to generate the majority of the ATP during aerobic respiration.

Aerobic respiration requires oxygen, however, there are many organisms that live in places where oxygen is not readily available or where other chemicals overwhelm the environment. Extremophiles are bacteria that can live in places such as deep ocean hydrothermal vents or underwater caves. Rather than using oxygen to undergo cellular respiration, these organisms use inorganic acceptors such as nitrate or sulfur, which are more easily obtainable in these harsh environments.

This process is called anaerobic respiration. When oxygen is not present and cellular respiration cannot take place, a special anaerobic respiration called fermentation occurs. Fermentation starts with glycolysis to capture some of the energy stored in glucose into ATP. However, since oxidative phosphorylation does not occur, fermentation produces fewer ATP molecules than aerobic respiration.

In humans, fermentation occurs in red blood cells that lack mitochondria, as well in muscles during strenuous activity generating lactic acid as a byproduct, therefore it is named lactic acid fermentation. Some bacteria carry out lactic acid fermentation and are used to make products such as yogurt. In yeast, a process known as alcoholic fermentation generates ethanol and carbon dioxide as byproducts, and has been used by humans to ferment beverages or leaven dough.

Cellular respiration together with photosynthesis is a feature of the transfer of energy and matter, and highlights the interaction of organisms with their environment and other organisms in the community.

Cellular respiration takes place inside individual cells, however, at the scale of ecosystems, the exchange of oxygen and carbon dioxide through photosynthesis and cellular respiration affects atmospheric oxygen and carbon dioxide levels. Carbon di Oxide CO 2 , released in this process is utilized directly or indirectly in photosynthesis and produces carbohydrate food.

It involves stepwise intracellular oxidation of organic molecules into CO 2 , H 2 O water , and energy. This process helps plants in the absorption of water, which indirectly keeps running growth and other organic processes.

Many middle compounds of the procedure are helpful for other metabolic processes in the cells. The organic acid that produces in respiration is necessary for other organic activities, Respiratory energy also helps cell division.

It occurs only in those cells which contain mitochondria in the cell cytoplasm. Building larger molecules from smaller ones i.

The conserved energy ATP is made available for cellular activities. Importance of Anaerobic respiration : The significance of Anaerobic respiration are described below — Some Bacteria cannot live in the presence of oxygen. Among them, the only process of producing energy is anaerobic respiration. It is the energy-releasing and energy supplying catabolic procedure in anaerobic organisms.



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