Now remember, we classify our high energy molecules as being NADH, FADH2, and ATP. A way for us to remember where they're made within the Citric acid cycle is with memory tool 3. And it says that under trees in a forest, there lived 5 ants and 6 flies. So 'under' stands for NADH. 'Trees' we say 'threes'. In a forest, 'forest' for 4, 8. There lived 5 ants and 6 flies. Alright. So 'NAND' is NADH. NADH is created in reactions 3, 4, and 8 of the Citric Acid Cycle. And we're going to say here, that gives us what? In one round of TCA, that's 3 NADHs, but we go through it twice, so that's how we come up with 6 NADHs. There lived 5 ants, so it is in reaction 5 that we make ATP. And then here, 'F' for flies is FADH2. Which we make in reaction 6. So this is how we're able to remember what the high energy molecules created in the electron transport called the citric acid cycle are, and in which reactions they are made. So NADH is reactions 3, 4, and 8. ATP is reaction 5, and FADH2 is reaction 6.
Now, what is memory tool 4? Well, beside these 3 we also have the generation of CO2, carbon dioxide. Well, one CO2 is made in reactions 3 and 4. So just remember 1234. So 1 CO2 is created in reactions 3 and 4, giving us a total of 2 CO2s per round of the Citric Acid Cycle, which is a total of 4 CO2s when we go through the citric acid cycle twice. Right? So just keep these memory tools on hand. They'll help you remember what the high energy molecules are and which reactions create them.