Aerobic metabolism glycolysis

Pyruvate produced by glycolysis is a significant source of acetyl-CoA for the TCA cycle. Because, in eukaryotic ceils, glycolysis occurs in the cytoplasm, whereas the TCA cycle reactions and ail subsequent steps of aerobic metabolism take place in the mitochondria, pyruvate must first enter the mitochondria to enter the TCA cycle. The oxidative decarboxylation of pyruvate to acetyl-CoA,... 

Mitochondria are not permeable to NADH. However, reactions of glycolysis and other dehydrogenations in the cytoplasm quickly reduce available NAD+ to NADH. For aerobic metabolism to occur, the "reducing equivalents" from the NADH must be transferred into the mitochondria. Fungi and green plants have solved... 

Glycolysis involves the breakdown of energy-storage polysaccharides or glucose to the 3-carbon acid, pyruvate. Its function is to produce energy in the form of ATP and 3-carbon intermediates for further metabolism. Glycolysis occurs under both aerobic and anaerobic conditions. 

Brain function is dependent upon ready availability of energy by aerobic metabolism. This energy is provided by aerobic glycolysis, the breakdown of glucose blood sugar to pyruvic acid with 02 as an electron acceptor. Therefore, brain cells and other nerve cells are highly susceptible to interruptions in the supply of either 02 or blood glucose. 

The ATP can then power another contraction. Eventually, the amount of ATP available approaches a level too low to be bound by myosin in the muscle, even though it is by no means exhausted. The protons (acid) from metabolism cause hemoglobin to release its oxygen more readily, promoting a switch to aerobic metabolism. Lactate and protons from glycolysis may also lead to fatigue and an inability to sustain the level of speed that was possible earlier. In most humans, this seems to occur after a run of about 400 meters, which is why running quarters is one of the most unpleasant exercises for any athlete, no matter how well conditioned. 

As we emphasized above, the aerobic metabolic potential of muscle depends upon the integrated activities of several metabolic pathways (unlike the single pathway of glycolysis that is used in anaerobic work). So it is to be expected and is indeed observed (Holloszy and Booth, 1976) that increased respiratory capacity of muscle depends upon elevated activities of enzymes ... 

Reducing Equivalent Shuttles In aerobic metabolism NADH from glycolysis... 

Nucleoside triphosphates are the most common nucleotide used in metabolism. They are formed in the following manner. Recall that ATP is synthesized from ADP and P, during certain reactions in glycolysis and aerobic metabolism. ADP is synthesized from AMP in a reaction catalyzed by adenylate kinase ... 

Furthermore, the activity of phosphofructokinase (PFK), the enzyme that controls glycolysis by regulating Reaction 3, for instance, has been found to decrease sharply when switching from anaerobic to aerobic metabolism. This is said to... 

However, as distinguished from the aerobic metabolism of normal cells, cancer cell metabolism is in the main anaerobic and does not invoke the carboxylic acid cycle, dependent on oxygen and fimdamental to cell respiration, as set forth in Chapter 3 for glycolysis. Thus, respiration of the cancerous cell is excluded from consideration. Hence, from this standpoint, the anticancer claims for amygdalin or laetrile can be viewed as missing the mark. That is, under this interpretation, cyanide would affect aerobic normal cells but not anaerobic cancerous cells. 

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