3 types of respiration?

Yes, glycolysis; pentose phosphate pathway; and aerobic. Now things will get very complicated here so stick with us or check out our much simpler YouTube videos.
 
Glycolysis takes place in the cytosol of a cell, and it can be broken down into two main phases: the energy-requiring phase, above the dotted line in the image below, and the energy-releasing phase, below the dotted line.
 
Energy-requiring phase. In this phase, the starting molecule of glucose gets rearranged, and two phosphate groups are attached to it. The phosphate groups make the modified sugar—now called fructose-1,6-bisphosphate—unstable, allowing it to split in half and form two phosphate-bearing three-carbon sugars. Because the phosphates used in these steps come from ATP, two ATP molecules get used up. The three-carbon sugars formed when the unstable sugar breaks down are different from each other. Only one—glyceraldehyde-3-phosphate—can enter the following step. However, the unfavorable sugar, DHAP, can be easily converted into the favorable one, so both finish the pathway in the end.
 
Energy-releasing phase. In this phase, each three-carbon sugar is converted into another three-carbon molecule, pyruvate, through a series of reactions. In these reactions, two ATP molecules and one NADH molecule are made. Because this phase takes place twice, once for each of the two three-carbon sugars, it makes four ATP and two NADH overall. Each reaction in glycolysis is catalyzed by its own enzyme. The most important enzyme for regulation of glycolysis is phosphofructokinase, which catalyzes formation of the unstable, two-phosphate sugar molecule, fructose-1,6-bisphosphate. Phosphofructokinase speeds up or slows down glycolysis in response to the energy needs of the cell.
Overall, glycolysis converts one six-carbon molecule of glucose into two three-carbon molecules of pyruvate. The net products of this process are two molecules of ATP (4 ATP produced – 2 ATP used up) and two molecules of NADH.
 
The pentose phosphate pathway
This is the second form of respiration. PPP (Pentose phosphate pathway is very similar to the Calvin cycle, however where the Calvin cycle works on sugar synthesis, PPP works on degrading sugars. The compounds used in PPP could be shared with the Calvin cycle in theory if the processes occurred in the same place. The GAP produced by the PPP can enter glycolysis directly and potentially yield 19 ATPs after full aerobic respiration.
 
Aerobic respiration.
As plants make their own food by photosynthesis but they use aerobic respiration to release energy, aerobic respiration occurs in the opposite direction as photosynthesis is building up sugars at the same time as respiration is using them up.
 
Aerobic respiration occurs in the mitochondria and requires oxygen. Plant cells do not have mitochondria and therefore cannot respire using aerobic respiration.
Anaerobic respiration occurs in the cytoplasm, therefore plants do experience anaerobic respiration. They convert glucose into 3c (3 carbon) pyruvate through glycolysis. 3c pyruvate is then converted into ethanol + carbon dioxide through fermentation.
 

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