Review the effect of pH on enzyme function. Students should understand that enzymes function best at specific pH levels (which vary depending on the enzyme). Non-optimal pH levels can affect the shape of the enzyme, thereby decreasing its effectiveness as a catalyst. Extreme pH levels can permanently denature the enzyme protein, whereas less extreme pH conditions may only temporarily alter . Lactase is effective at pH 2 – 7 (including dH2O) and therefore breaks down the lactose sugar in milk into glucose and galactose.
II. Introduction Part 1: The Effects of Concentration on Enzyme Activity In this experiment, the effects of concentration on enzyme activity were determined by using a spectrophotometer to observe absorbance changes taking place in samples containing a pH 5 buffer, guaiacol, hydrogen peroxide, and different volumes of potato extract. Hypotheses Ho: The amount of enzyme added does not influence the rate of reaction. Ha: The amount of enzyme added does influence the rate of reaction. Part 2: The Effects of Temperature on Enzyme Activity In this experiment, the effects of temperature on peroxidase activity were determined by using a spectrophotometer to observe absorbance changes taking place in temperature treated samples containing potato extract, guaiacol, hydrogen peroxide, and pH 5 buffer.
Water potential is the concept used to combine the differences in solute concentration and pressure to predict the direction in which water will diffuse through the living plant tissue and states that the net movement of water will always be from an area of higher water potential to and area of lower water potential. Water potential can be confirmed by taking the graph of the data. This data can be used to experimentally determine the value for C (molar concentration of sucrose at equilibrium) in order to determine a value for Ψs (Ψs =solute potential). Variable Table: Variable | Unit | How to Control | Independent- Sucrose Concentration | 100mL with varying Molarities (0.0M, 0.2M, 0.4M, 0.6M, 0.8M, 1.0M) | Premade solutions by lab tech so should be correct. However, will label test tubes with correct Molarities so no confusion occurs.
The familiar volcano experiment that we all know, mixing baking soda and vinegar, is used to create a bubbly reaction. In the lab, two substances are mixed and create sodium acetate, carbon dioxide, and water (CH3COOH). The purpose of the lab was to predict how much product was made from the chemical reaction, using stoichiometry. If there is a certain amount of baking soda, mixed with 50 mL of vinegar, then the percent yield will be able to be predicted. The percent yield gained was calculated from the amount that was recovered from the experiment.
1) ABSTRACT The purpose of this experiment was to carry out the effects of enzyme concentration, temperature, pH level, and an inhibitor on a type of enzyme called Perixodase. The purpose of the experiment was also to understand the relationship between the change in absorbance with time and the enzyme reaction rate. To perform the experiment, the class was divided into groups. Each group took on one of the factors affecting the enzyme. Before beginning the actual experiment, we used the mixing tables that were given to us to set up the test tubes with the appropriate substances.
If we place the potato in a sucrose solution with a similar solute concentration as a potato, then the least amount of water will diffuse into or out of the potato cells. This occurs because this scenario will be initially closest to an isotonic solution, allowing us to determine the solute concentration of a potato. Materials: * Knife/ Cork Borer * Seven 30 cm pieces of Dialysis tubing * Thirteen 250 mL Beakers * 15% Glucose Solution * Glucose Test Strips * 1% Starch Solution * Distilled water * Lugol’s solution * 25 mL of: * .2 M sucrose * .4 M sucrose * .6 M sucrose * .8 M sucrose * 1 M sucrose * Paper Towels * Clock * Potatoes * Plastic
They are used to speed up the reaction rates by providing an alternative reaction pathway of lower activation energy, which is the minimum energy that requires for reactions occur. Catalysts take part in a reaction (chemical involved), but they do not undergo any changes in chemical reaction. (Farabee, 2001) Enzymes are proteins made of a combination of different amino acids. Therefore, the enzymes may be lost
We let them soak for 20 minutes than we removed them from the test tubes. Next we measured their new weights and recorded them. They were; 10% NaCl decreased by 4%, 15% NaCl decreased by 8%, and 20% NaCl decreased by 12.5%.The results showed us the conclusion that the potatoes were hypertonic to the deionized water and were hypotonic to the sodium chloride solutions. Introduction: The objective of this experiment is to detect diffusion and osmosis in potato cells in 3 solutions. Diffusion is the spontaneous spread of molecules from an area of high concentration to an area of low concentration.
Effect of Surface Area to Volume Ratio on Diffusion Rate of Glucose from Potatoes Abstract: The experiment was conducted to determine if differences in surface area had a significant effect on diffusion rate of glucose from potatoes. Potato samples of three different lengths were collected through a process of coring along the middle of the vegetable. Cores were soaked in distilled water for a period before an o-dianisidine-enzyme solution was added. Glucose diffusion rates were determined by using a spectrometer after a period of incubation of the potato samples. Glucose levels were measured at 0.52, 0.57, and 0.67 showing that an increase in surface area corresponded with a non-significant (p=0.096) increase in the glucose diffusion rate.
Controlled Variables. temperature; pH; sucrase + sucrose incubation time 4. Describe what is measured as an indicator of sucrase activity and why this is an indicator of sucrase activity. The amount of product produced is an indicator of sucrase activity. This is an indicatore because sucrase is an enzyme found in the small intestine that catalyzes the splitting of the disaccharide sucrose into the monosaccharides glucos and fructose.