Yeast Fermentation Lab Report

There are many substances that can be manipulated and cause the rate of reaction in fermentation to either speed up or slow down. Substances that alter the rate of the reaction could be temperature of the water, the yeast concentration, pH, and the glucose concentration. In the experimental group of the experiment the amount of yeast concentration was manipulated. The objective of this experiment was to determine what factors affect the rate of the fermentation. To test this objective we changed the amount of yeast being used. A higher yeast concentration replaced the controlled yeast amount. A prediction made by my group was that higher amount of yeast would speed up the process of fermentation. Our null hypothesis is there will be no

Fermentation is a metabolic pathway that produce ATP molecules under anaerobic conditions (only undergoes glycolysis), NAD+ is used directly in glycolysis to form ATP molecules, which is not as efficient as cellular respiration because only 2ATP molecules are formed during the glycolysis. One type of fermentation is alcohol fermentation, it produces pyruvate molecules made by glycolysis and the yeast will break it down to give off carbon dioxide, the reactant is glucose and the byproducts are ethanol and carbon dioxide. In this lab, the purpose is to measure whether the changes of

The purpose of this investigation is to test the effect of different sugar sources on yeast respiration.

Hypothesis: If the concentration of an substrate is increased then the time it takes for the yeast spheres to rise will decrease because there is more substrate for the enzyme to break down, creating more oxygen, faster.

Abstract: This lab’s purpose was to see how different levels of yeast, distilled water, and sugar interact to affect the level of carbon dioxide evolved in fermentation. In this experiment we had two sections. The first section tested four test tubes with varying levels of yeast, glucose and distilled water for evolved carbon dioxide levels. The tubes were timed for 20 minutes. The amounts of solution in the test tubes are noted in the methods section of this lab report. The second section of the lab used three test tubes and flowed the same procedure except added spices. The levels of ingredients are also in the methods section. The main goal of this experiment was to see the effects of yeast concentration.

During this experiment, sugar sources were varied and respiration rate evaluated. To begin, a water bath was set at 30 degrees Celsius. This creates an optimum temperature for the enzymes in yeast to breakdown sugar and give off CO₂. Each sugar source, glucose, sucrose, lactose and glycerol were all added to its own unique yeast sample, one at a time. Each sugar source that was added to the yeast solution was immediately incubated for 10 min, then was transferred to a respiration chamber. The CO₂ sensor was put in, recording the CO₂ respiration for 4 min. This process was done for each sugar source. The reparation rate was recorded through Logger Pro. After 4 min passed, the slope was recorded, resulting in respiration rate.

There are many processes that are needed to occur to produce something that help organisms live. Cellular respiration and fermentation are two process that are important to the survival of organisms. Cellular respiration is the way cells make ATP, which they need to survive. The process starts with the breaking down of glucose into other compounds that can be used by the cell. However, there are more steps in the process than just cellular respiration and how precise cellular respiration is depends on how much ATP can be taken from food particles in the body (Hill 646). Fermentation is mostly known in the world of beer and wine, but it also produces lactate in organisms. Fermentation is breaking glucose into separate components like water or carbon dioxide, much like that of cellular respiration. N’guessan and some peers did an experiment and they found that after fermentation had stopped, they had over 200 counts of yeast in the beer (N’guess, Brou, Casaregola, Dje 858). Under the

This lab investigates the effects of Sucrose concentration on cell respiration in yeast. Yeast produces ethyl alcohol and CO2 as a byproduct of anaerobic cellular respiration, so we measured the rate of cellular respiration by the amount of CO2

The CO2 production was measured with a CO2 meter (+/- 1ppm), in order to determine the rate of anaerobic cell respiration in yeast.

1. Lab reports are to be computer-generated and double-spaced. All sections of the report must

Hypothesis: The yeast will have a greater rate of respiration for the natural sugars specifically the glucose and lower rate of respiration for the unnatural sugars

For the experiment, the changes of temperature on anaerobic fermentation the process in which cells undergo respiration without oxygen in Saccharomyces cerevisiae was observed. The purpose of this experiment was to test the effect of four different temperatures on the rate of carbon dioxide production in yeast by measuring the fermentation rate. Saccharomyces cereviviae, also known as Baker 's yeast, is a unicellular, eukaryotic sac fungus and is good for this experiment because of its characteristic of alcohol fermentation. It was hypothesized that fermentation increases with increased temperature to a point of 37°C; above that point, enzyme denaturing will occur and fermentation will decrease. The group was able to document the carbon dioxide production and mark each of the temperature intervals which were tested at temperatures 4°C (refrigerator temperature), 23°C (Room temperature), 37°C (Human body temperature) and 65° Celsius (Equal to 150°F). The experiment was conducted by pouring yeast solution with 2% glucose in fermentation tubes, placing the tubes in the appropriate incubation temperature, marking the rise of the gas bubbles in the fermentation tubes which indicated carbon dioxide production. The results of this experiment were not supported by the hypothesis, creating different results from what was predicted. It is important to understand the fermentation rate of yeast so

Table 1: Table of Results Showing the Effect of Yeast Mass on the Rate of Yeast-Facilitated Fermentation of Glucose

Sugars are vital to all living organisms. The eukaryotic fungi, yeast, have the ability to use some, but not all sugars as a food source by metabolizing sugar in two ways, aerobically, with the aid of oxygen, or anaerobically, without oxygen. The decomposition reaction that takes place when yeast breaks down the hydrocarbon molecules is called cell respiration. As the aerobic respiration breaks down glucose to form viable ATP, oxygen gas is consumed and carbon dioxide is produced. This lab focuses on studying the rate of cellular respiration of saccharomyces cerevisiae, baker’s yeast, in an aerobic environment with glucose, sucrose, lactose, artificial sweetener, and water as a negative control. A CO2

Rate of Respiration in Yeast Aim: I am going to investigate the rate of respiration of yeast cells in the presence of two different sugar solutions: glucose, sucrose. I will examine the two solutions seeing which one makes the yeast respire faster. I will be able to tell which sugar solution is faster at making the yeast respire by counting the number of bubbles passed through 20cm of water after the yeast and glucose solutions have been mixed. Prediction: I predict that the glucose solution will provide the yeast with a better medium by which it will produce a faster rate of respiration.