We have now learned about cellular respiration. This, in my opinion, really makes everything we have been learning about this year click. Cellular respiration consists of 3-4 steps: glycolysis, the Krebs cycle (aka the Citric Acid Cycle), and oxidative phosphorylation. Fermentation is an optional step, and only occurs in certain circumstances. All of these steps are focused on making energy for the body, so it takes place mainly in the mitochondria. It uses proteins in the fluid mosaic model (which I understand much better now) to help process the hydrogen ions and electrons during the last step to make ATP. We will learn about photosynthesis soon – hopefully that will make everything click!