Lilli Powell
13 March 2016
119L-03
Logan Williamson and Joseph Patterson
Abstract: Fermentation happens when an anaerobic reaction occurs. This lab was testing to see how different pHs effect the rate of CO2 produced by an anaerobic reaction. Five Smith fermentation tubes had a mixture of glucose and yeast organisms of various different pHs. After the tubes were thoroughly mixed and their pHs tested and recorded, they were set aside to be analyzed for ten minutes. Then with a millimeter ruler, the amount of CO2 produced was measured from the outside of the tube. This was repeated five more times; to conclude the process, …show more content…
Yeast cells produce acidic solutions as well as alcohol, so the buffers are used to keep the stated pH constant (Reece, 2014). Glycolysis makes ATP, but when there is no oxygen to go into the mitochondria; fermentation makes it possible to continually produced ATP. By oxidizing the NADH produced in glycolysis, fermentation regenerates NAD+, which can take part in glycolysis once again to produce more ATP (Pearson, 2016). This is very important because living organism must always be producing energy for the synthesis of biomolecules, general movement, and maintaining osmotic gradients with in cells (Stallsmith, 2014). The hypothesis for this experiment was that the amount of hydrogen ions would affect the pH of the different solutions, which would affect the efficiency of …show more content…
Then in each of the tubes 12 ml of the yeast solution (38 ml of glucose + 41.25 g. yeast/750 ml) was added, along with five specific buffers to each specific tube as followed: tube 1 had 12 ml pH 3 buffer added, tube 2 had 12 ml pH 4 buffer added, tube 3 had 12 ml pH 6 buffer added, tube 4 had 12 ml pH 7 buffer added, and tube 5 had 12 ml pH 8 buffer added. After the solutions were well mixed – by putting a thumb on the opening of the Smith fermentation tube and turning the tube, moving around the air pocket collected within the tube – the pH was collected from each tube and recorded. Then for the next 60 minutes, every 10 minutes the tubes were measured (in mm) from the top of the tube to the beginning of the solution in the tube and recorded for the period of time. Once the 60 minutes were expired, the final pH of each solution was collected and