The Ability of Yeast to Ferment Sugar Molecules

All cells need to have a changeless ability supply. The two processes by which this energy is attained from photosynthetic materials to pretend ATP are cellular respiration and processing. (Hyde,2012). Fermentation is a track of harvesting chemical energy that does not require oxygen. (Reece et al. 2012). When the body is deprived of oxygen it will and so begin to meet its energy postulate by with(p scarleticate) the slow process of unrest. In our lab we investigated alcoholic fermentation by using barm, which can flourish in an low energy environment in an aerobic conditions.In this lab our goal was to discover the put at which yeast will ferment different sized molecules of carbohydrates. In order to perform our try out we make use of irrigate, glucose, sucrose, and stiffen. It was hypothesized that glucose, sucrose, then starch would all be used to produce energy during fermentation. Being that glucose is a simple sugar, or monosaccharide, we predicted that glucos e would be fermented to the highest degree quickly. This hypothesis was made ground on the idea that glucose is the cells main lineage of energy in aerobic cellular respiration. The first step of cellular respiration is glycolysis which dampens agglomerate glucose for energy.We predicted that sucrose would ferment second to glucose since it is a larger molecule composed of glucose and fructose. Finally, we predicted that starch would ferment extremely slow behind all of the other carbohydrates. METHODS AND MATERIALS On October 31, 2012 in the lab of Greenfield Community College my lab partners, Madeline Hawes, Timothy Walsh and I conducted the side by side(p) experiment in order to test the effectiveness of yeasts ability to ferment different carbohydrates. We first fill up 6 small flaskfuls with 75 ml of water and 5 drops of phenol red to for each one flask.Four of these were labeled with the result that would feed into them and the other two with swear and the last with increased CO2. The tinct of phenol red is orangish- knock when there is a neutral pH present. As carbon dioxide is released into this ancestor from the release of the gas from the yeast filled flasks, the response turns a light yellow indicating a weak acid. We measured forbidden four weigh boats of 2 grams each of starch and then added 2 grams to each of 4 labeled flasks of 50 ml water, 50 ml Glucose source, 50 ml Sucrose solution, and 50 ml Starch solution respectively.All of these had been stored in incubators to maintain an optimal temperature of 35 degrees celsius. We put these flasks into our sink which we made into a water bath. We then drained and added hot plate warm water from a 1000 ml beaker we kept heated in order to maintain the optimal temperature of 35 degrees celsius around the flasks. We swirled the large flasks to intermingle the solutions and yeast as they sat in the water bath. The flasks containing the yeasts solutions were then stopper with glass straw s and tubings and their extending thermionic vacuum tubes placed into the matching labeled smaller flasks adjacent to the sink.I blew through a straw into the flask labeled increased CO2. The phenol red detected the presence of CO2 turning the solution yellow. The control flask was left as a comparison for the remaining yeast filled tubes feeding into the other flasks of phenol red and water. RESULTS We recorded our first observations at 10 minutes. Just as we hypothesized, the yeast and water experienced no change. In the glucose solution flask, the glucose molecules were being quickly broken down and forming a frothy head, sending a bubble of CO2 through the tube all(prenominal) 2 seconds while turning the phenol red to a light orange.The sucrose solution was bubbling every three seconds and as well had turned light orange. At 10 minutes there was no reaction in the Starch solution. The latter data remained consistent with our hypotheses. The glucose solution at 20 minutes wa s very frothy and bubbly and had turned the phenol red a very light yellow with a consistent bubble through the tube every second indicating a strong presence of CO2. The sucrose, too, had turned light yellow and had continuous bubbles every 2 seconds. The starch had a rare bubble with no noted change in the phenol red solution.At the final check in of 40 minutes both the glucose and sucrose had fermented most of the yeast and slowed down on bubbling. The glucose still had the most bubbles occuring. The starch was a lighter pink with little change in the levels of froth in the yeast solution. The water solution still remained completely unchanged. DISCUSSION Our hypotheses were supported through illustrating that all forms of sugar do provide energy and that glucose, being the smallest molecule, was the most efficient. The control tube contained no sugar and therefore produced no energy. A source of sugar is necessary for glycolysis and fermentation to occur.The strongest presence of carbon dioxide was in glucose, indicated by the bubbles which are a by-product of ethanol fermentation. The rate of fermentation in sucrose was second to glucose and Starch was the least effective at providing a sugar to create energy. The large polysaccharide was difficult for yeast to break down to create the necessary energy that would produce carbon dioxide. Glucose is the most efficient sugar as it is a small monosaccharide which is already the source of energy for the Glycolysis cycle. The largest possible source of error in our experiment is the time in which each solution began its fermentation process.We added the yeast into each flask containing the sugar solutions at staggered generation. If this experiment were to be repeated it would be more precise to have four people pour in the yeast and swirl at the exact same time and then stopper the solutions. The only minor inconsistency would be the amount of yeast that was spilled or left in the weigh boats. This could cre ate a strain in the final results. Through this lab I understoodd that in times of oxygen deprivation the body can still function through the process of fermentation.The yield of 2 ATP molecules is enough to keep muscles assure for a short period of time when oxygen is scarce. Through the fermentation process NAD+ is regenerated as pyruvate is broken down to CO2 and ethanol. This allows the anaerobiotic production of 2 ATP molecules. (Reece et al. 2012). In essence, keeping cells alive that whitethorn otherwise die without the energy to provide for muscle contractions of the heart.LITERATURE CITED Reece, Taylor, Simon, Dickey, and Campbell. , Biology concepts & connections. Pearson gum benjamin Cummings, San Francisco, CA. Pgs. 100-101 Hyde, A. October 31, 2012