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Cellular Respiration

Cellular respiration occurs in the mitochondria, where nutritional energy is converted to adenosine triphosphate (ATP), known as the 'energy currency' of biological systems. One molecule of ATP has three phosphate groups which are converted to adenosine diphosphate (ADP) and adenosine monophosphate (AMP) and back to ATP during the various stages. Respiration is an exothermic catabolic process, where larger units of energy at broken into smaller units for cell utilization, and additionally the process releases heat. Aerobic respiration requires the presence of oxygen, whilst anaerobic does not.

There are three main stages of cellular respiration: glycolysis, Krebs cycle and oxidative phosphorylation (electron flow). Glycolysis occurs in the cytoplasm of the cell, this is where one glucose molecule (C6H12O6) is converted to two molecules of pyruvate, and also the production of 2 ATP. The pyruvates are converted to acetyl-coenzyme A, where then it enters the Krebs cycle or the Citric acid cycle in the mitochondrial matrix. Acetyl-coenzyme A is then oxidized to produce 6 NADH, 2 FADH2 and 2 ATP in many stages, with waste products of CO2 and H2O. In the mitochondrial cristae, oxidative phosphorylation converts the remaining products to 34 ATP units by using the electron transport chain (ETC) with a proton gradient. In total, one molecule of glucose produces 38 ATP units.  

Without the presence of oxygen, the two pyruvates undergo fermentation in the cell cytoplasm to produce lactic acid and carbon dioxide. Fermentation only produces 2 ATP from one glucose molecule. Fermentation is popularly known for the production of ethanol (C2H6O) in industry. 

Categories within Cellular Respiration

Glycolysis

Postings: 4

Glycolysis is the first step in both aerobic and anaerobic cellular respiration, it will occur in the cytoplasm of the cell with or without the presence of oxygen.

Krebs Cycle

Postings: 4

The Krebs cycle requires oxygen to function, so it is an integral pathway for all aerobic organisms to generate ATP.

Electron Flow

Postings: 7

Electron flow is the movement of electrons down a electrochemical proton gradient to generate ATP in the inner mitochondrial membrane.

Aerobic Respiration

Postings: 9

Aerobic Respiration is the production of large amounts of ATP from pyruvate by Glycolysis, Krebs Cycle and Electron Flow.

Anaerobic Respiration

Postings: 4

Anaerobic Respiration does not use oxygen, but instead uses less-reductive substances to produce ATP in either Homolactic or yeast fermentation.

Exercise routine utilizing each of the three major energy pathways

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Discussion of Various Cellular Respiration Questions

1. CO2 that we respire was originally part of biological molecules that have been oxidized. Explain this observation to someone who has not had any biology. 2. If in an experiment, protons could somehow rapidly be removed from the inner membrane space, how would this affect synthesis by electron transport? 3. If the inner

Discussion of Cellular Respiration.

Describe the process by which food energy is converted into the chemical energy of ATP in living cells. Go through each of the major steps in the process, including the starting and ending product of each step, and any important molecules produced or consumed. Include one or more labeled diagrams to help explain your answer.

Chemiosmotic Theory/ATP/Earth's Cycles/Hypertheromphiles

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The impact of physical activity on cellular respiration

Hello. I am trying to do my homework for this week and I have no idea how to answer this question. Here is the question... What is the impact of physical activity on cellular respiration? Why do we need to cool our bodies by sweating when exercising?

Cellular Respiration Explained

Briefly explain the process of cellular respiration and uses of the energy obtained from the process. Your answer should include the following terms: glucose, water, carbon dioxide, chemical energy, and oxygen. What organisms carry on this process?

Carbon Tracking in TCA Cycle

C14-Glucose labeled at carbon 5 enters glycolysis, is made into pyruvate, then acetyl CoA, and enters the TCA cycle. How much of the C14 will be released as CO2 during the second turn of the TCA cycle?

Moles of ATP from Oxidation of Ethanol

Given the info below, what is the number of moles of ATP that could be synthesized from ADP and Pi (deltaG° = 7700 cal/mol) upon complete oxidation of one mole of ethanol to 2 CO2 and 3 H2O? (with an assumed efficiency of 37%) Glucose ---> 2 ethanol + 2 CO2 deltaG°= -55,000 cal/mol Glucose + 6 O2 ---> 6C

Oxidation of Succinate and Malate

Why is the oxidation of succinate to fumarate only associated with the production of two ATPs during oxidative phosphorylation, whereas the oxidation of malate to oxaloacetate is associated with the production of three ATPs?

TCA Cycle Function and Reactions

In the mammalian CNS there is a pyridoxal phosphate dependent glutamate decarboxylase that catalyzes the conversion of glutamate to gamma-amino butyric acid (GABA). This is an important inhibitory neurotransmitter. GABA is subsequently degraded through transamination to succinic semialdehyde, with alpha-ketoglutarate as the

Measuring cellular respiration is achieved.

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