The second unit 2 of our Ap Biology course was mainly about a cell. From my background of learning at Liger for 6 years, I exposed a lot to the science field related cell. For the introduction part of learning about each organelle’s function was mainly review. However, after completed the cell unit there were so many exciting concepts that I enjoyed learning about. The new concepts that I enjoyed learning the most were the signaling transduction pathway, cellular respiration, fermentation, and photosynthesis. Cells are smart and really complex to understand, especially, the concepts listed above. But how each processed form was really unique and precise. For instance, the process of signaling transduction pathway is that in order for a reaction to happen it requires a different step; the ligand has to bind with the protein receptor which creates another process of reaction. And the process in the transduction will continue to create another reaction until the final step for the cell to response the signal. At the same time, we had a minilab of fermentation. We set up an experiment of yeast and different sources of sugar and placed it together in different flasks. After two hours of experiment, I saw the ballon with air inside which was carbon dioxide. Furthermore, we had another mini lab to understand the concept of photosynthesis since one of the product from the light-reaction was oxygen. So for our experiment, we set up a leave inside the water and leave it under the sunlight. It turned out the lab was working, I was surprised when a small so many tiny bubbles which indicate the oxygen as a waste product from photosynthesis.