Enzyme Lab

3. What effect does boiling the liver have on the action of the enzyme? Explain why.

The more acidic a substance is the less oxygen it will produce when going through a chemical reaction. During the Lab “How Do Changes in pH Levels Affect Enzymes Activity”, the researcher conducted an experiment to test the effects that an acidic, neutral, and a base substance will have when combine it with hydrogen peroxide. The data table shows that HCL (acidic substance) barley produced any oxygen at all when it was combining with Hydrogen Peroxide. The pH level for HCL was 2.5; this level indicates that the substance was very acidic. When the H2O and NaOH were tested they produced more bubbles than HCL. NaoH produced a little more bubbles than HCL. The pH that NaoH produced was a 9, which is a base. H2O produced more bubbles than both substances;

1. We measured 2 mL of diluted hydrogen peroxide (the substrate), 1 mL of guaiacol (the product indicator), and 1 mL of neutral buffer (pH 7) with a syringe and disposed it into tubes 1, 2 , 4, 9, 11, and 12.

These results show how temperature of extreme high, or low affects enzyme activity. The highest rate of enzyme activity occurred at 37 Cº. Anything that was hotter or cold than 37 Cº slowed the reaction rate. As I thought, 100 degrees would denature the enzyme, and that was the case. The data provided shows exactly what temperatures enzymes work best, and worst. The objective was achieved as we discovered the different reaction rates under different temperatures. The results are reliable, as we know enzymes do not work well when under extreme heat or denaturation occurs. What I learned in this experiment was that enzymes don’t work well under cold temperatures because they tend to move slower. My hypothesis did not quite match, because I thought they work best at lower temperatures.

As stated in the introduction, three conditions that may affect enzyme activity are salinity, temperature, and pH. In experiment two, we explored how temperature can affect enzymatic activity. Since most enzymes function best at their optimum temperature or room temperature, it was expected that the best reaction is in this environment. The higher the temperature that faster the reaction unless the enzyme is denatured because it is too hot. Similarly, pH and salinity can affect enzyme activity.

Submerge the graduated cylinder in the plastic tub so that it is completely filled with water. Hold the open end of the graduated cylinder and move it vertically upside-down where the open end of the graduated cylinder is still submerged in the plastic tub. Clamp the graduated cylinder the ring stand of the lab table to keep it in place. perforate a hole in the top of the rubber cork for the solution container. Cut a straw the length of about four inches. place the straw inside of the rubber cork hole. Set up your timer for two minutes.

Enzymes are a key aspect in our everyday life and are a key to sustaining life. They are biological catalysts that help speed up the rate of reactions. They do this by lowering the activation energy of chemical reactions (Biology Department, 2011).

9. 2.5 cm 3 of hydrogen peroxide, H2O2 was added into the test tube and immediately, the stopper of the bung is placed into the test tube.

generally act as a catalase that initially bring about a chemical reaction.” Enzymes play an

The 10 mL measuring cylinder was used to measure 5 mL of the hydrogen peroxide solution into the test tubes labelled 1, 2, 3, 4 and 5.

As we study biomolecules, the subject of how do enzymes work comes up. The reasoning behind the catalase enzyme lab was to see how enzymes break down compounds. My objective being to see how the catalase enzyme will react to liver, potato and apple. We will also use a base or acid to see how these factors will affect the independent variable. My hypothesis is the liver and potato will react to the peroxide but the apple will not.

The chemical hydrogen peroxide(H₂O₂) is broken down by the enzyme catalase. Hydrogen peroxide is a byproduct formed in cellular reactions that, if not broken down, could inflict severe damage to the cell. Catalase is an enzyme that breaks down hydrogen peroxide in to water and oxygen. How efficient and strong the enzymes reaction to break down H₂O₂ determines largely on temperature and pH level. An enzyme only functions within a set pH and temperature range. Beyond that it becomes denatured, rendering it useless. The purpose of this lab is to determine at which temperature and pH level the enzyme catalase reacts best. Catalase in chicken and beef livers will be used to do the lab because enzymes still function after death as long as they are kept refrigerated at a low temperature.

First, three small pieces of liver were placed into separate test tubes and covered with a small

4.Measure 35mL of warm water and add them into each of the 4 test tubes at about roughly the same time. It is essential that the water is warm. Do not seal the test tube.

Then, the test tubes were placed in the test tube rack. A plastic dropper was used to measure the number of drops that were deposited in every test tube. To test for temperature and for pH levels, in the number one test tube, twenty drops of Hydrochloric Acid (HCL) were added. For the number two test tube, twenty drops of water (H2O) were added. For the number three test tube, twenty drops of sodium hydroxide (NaOH) were added.