Cellular respiration is how heterotrophs turn food consumed into useable energy. Cellular respiration is broken down into four phases, the first one being Glycolysis. Glycolysis takes place in the cytoplasm and is the only anaerobic process in cellular respiration. Glycolysis starts with a 6 carbon molecule called glucose. Two ATP are then added to the reaction which forms two ADP to be recycled, and two phosphate molecules added onto your 6 carbon glucose. The energy added also splits the 6 carbon glucose into two 3 carbon molecules called G3P. Next two of the coenzyme NAD+ is added the equation, they pick up four electrons and two hydrogen ions giving you two molecules of NADH to be used in one of the later phases. At the same time another phosphate is added onto the G3Ps giving you two 3 carbon molecules both with two phosphate groups attached to them. Now the ADP that was to be …show more content…
The Krebs cycle also occurs in the mitochondria but this time in the mitochondrion matrix. The first step of this phase is taking the product from the last phase, the acetyl-CoA, and combining it with a 4 carbon molecule giving you a 6 carbon molecule called citric acid. The citric acid cycle turns once for every molecule of pyruvate so all the inputs from here on out should be multiplied by two for your final count. After the citric acid is formed three NAD+ molecules come in and take their standard two electrons and one hydrogen ion for every molecule and give you three molecules of NADH. While that is occurring two molecules of carbon dioxide are released, and one ADP molecule gets a phosphate group added to it synthesizing one ATP molecule. Also a molecule like NAD+ called FAD gains electrons and two hydrogen ions to become FADH2. So if that was a little hard to follow the end product of the Krebs cycle for each molecule of pyruvate is: three NADH, two CO2, one ATP, and one FADH2