Yeast are single-celled fungi. Yeast cells use an aerobic process called alcoholic fermentation to produce energy in the form of ATP. Not only does this process convert glucose into ATP, but it also produces ethanol and carbon dioxide. Along with a few other classmates, I performed the “alcoholic fermentation in yeast” lab to find the ideal conditions for carbon dioxide production in yeast. Organisms obtain the energy they need from food. Yeast cells use sugars, such as glucose, as a food source. However, because glucose cannot be used directly by organisms, glucose molecules have to go through the process of glycolysis. During glycolysis, one molecule of glucose gets broken down into two pyruvic acid molecules. Along with the two pyruvate
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Enzymes are considered to be “biological catalysts” meaning they can speed up a chemical reaction in a cell. In alcoholic fermentation, enzymes break down starch into simple sugars that can be used by yeast. Alcoholic fermentation wouldn’t be possible without enzymes. Temperature can also greatly affect fermentation. If the temperature used for fermentation is too high, then the yeast cells can actually start to die. According to The Artisan, the optimum temperature for fermentation is 35 ℃. Enzymes actually affect the optimum temperature for fermentation. As the temperature increases, the rate of alcohol fermentation increases as well. However, once the temperature gets too high, the enzymes become affected and can’t increase the rate of the reaction. In fact, the rate of the reaction quickly decreases. For the first week of this experiment, we tested three different groups of yeast and water. In the first group, we tested four grams of living yeast cells in plain water. In the second group, we tested four grams of living yeast cells in sugar water, which contained .5 grams of sucrose. In the third group, we tested four grams of dead yeast cells in sugar water, which also contained .5 grams of sucrose. We were instructed to add the yeast and sucrose, depending on the group, in 80 mL of 35℃ water. However, my group left the water out for too long, and our starting temperature was 28℃. After stirring the yeast and
Enzymes are considered to be “biological catalysts” meaning they can speed up a chemical reaction in a cell. In alcoholic fermentation, enzymes break down starch into simple sugars that can be used by yeast. Alcoholic fermentation wouldn’t be possible without enzymes. Temperature can also greatly affect fermentation. If the temperature used for fermentation is too high, then the yeast cells can actually start to die. According to The Artisan, the optimum temperature for fermentation is 35 ℃. Enzymes actually affect the optimum temperature for fermentation. As the temperature increases, the rate of alcohol fermentation increases as well. However, once the temperature gets too high, the enzymes become affected and can’t increase the rate of the reaction. In fact, the rate of the reaction quickly decreases. For the first week of this experiment, we tested three different groups of yeast and water. In the first group, we tested four grams of living yeast cells in plain water. In the second group, we tested four grams of living yeast cells in sugar water, which contained .5 grams of sucrose. In the third group, we tested four grams of dead yeast cells in sugar water, which also contained .5 grams of sucrose. We were instructed to add the yeast and sucrose, depending on the group, in 80 mL of 35℃ water. However, my group left the water out for too long, and our starting temperature was 28℃. After stirring the yeast and