Enzymes Lab Report PDF

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Lab report and explanations about different kinds of enzymes...

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Enzymes Morgan Fortner Lab Partners: Alexis Perricelli & Vanessa Bremmer Due October 25, 2016 BY 110-07

I certify that this work is solely my own, and any outside source was paraphrased and properly cited. Signature:

Introduction An enzyme is a type of macromolecule known as a protein. Proteins are made up of amino acids. In a reaction, a substrate binds to a substrate’s activation site. Sometimes the reaction is sped up by a substance called a catalyst. In section two of this experiment, we tested the relationship between substances and their foam layer thickness after the addition of hydrogen peroxide. If an observable foam layer is present along the top of the substance, then the substance contains a digestive enzyme capable of breaking down hydrogen peroxide thus participating in metabolic activity. In section three, we tested the action of catalase in both plant and animal tissue with the hypothesis being that all cells equally break down hydrogen peroxide. Plant cells and animal cells may be similar but they are not the same. Plant cells have some different structures than that of animal cells that perform different functions. In section four, we tested the effect of temperature on the action of catalase in liver cells with the hypothesis being that temperature has no effect on catalase activity. In section five we created our own hypothesis. We hypothesized that adding pH to catalase in liver cells will increase the thickness of foam. Normally when an enzyme is exposed to high temperatures or changes in pH, the structure is altered thus altering the function or preventing the enzyme from performing its tasks rendering it useless. Method Section One: Cut a piece of tissue with a scalpel that will later be grinded up in order to free up the enzyme. Put the piece of tissue in the mortar. Add a small amount of sand and then add at least 1ml of water to the mortar. Grind up the tissue in the mortar until you physically can’t anymore; it should be in liquid form. Make sure to use only 50 microliters of the liquid tissue while conducting the experiment.

Section Two: Prepare four test tubes. Test tube one contain have a spatula of and. Test tube two should contain 2ml of water. Test tube three should contain a spatula of MnO2. Test tube four should contain 50 microliters of liver extract. Add 1ml of water and 1ml of hydrogen peroxide to each test tube then observe. Using millimeters (mm) as the unit of measurement, observe and measure the amount of foam produced at the top of each substance. Section Three: Prepare four test tubes. Test tube one should contain 50 microliters of apple tissue extract and 1ml of water. Test tube two should contain 50 microliters of potato tissue extract and 1ml of water. Test tube three contain have 50 microliters of beef steak extract and 1 ml of water. Test tube four should contain 50 microliters of beef liver extract and 1 ml of water. Once the test tubes are prepared properly, add 1ml of hydrogen peroxide t each test tube. Observe and measure the thickness of foam along the top of the solutions. Section Four: Prepare four test tubes. Put 50 microliters of liver tissue extract in each test tube along with 1 ml of water. Add 1ml of hydrogen peroxide to each test tube. Expose each test tube to its designated temperature. Test tube one should be exposed to 0C for five minutes. Test tube two should be exposed to 20C for five minutes. Test tube three should be exposed to 37C for five minutes. Test tube four should be exposed to 100C for five minutes. After approximately five minutes add the hydrogen peroxide to each test tube and measure the thickness of the foam layer that has formed along the top of the substance. Section Five: Prepare five test tubes. Add 50 microliters of liver cell tissue extract to each test tube. Add 1ml of hydrogen peroxide to each test tube. Add 1 ml of a 2 pH buffer solution to test tube one. Add 1ml of a 4 pH buffer solution to test tube two. Add 1ml of a 6 pH buffer solution to test tube three. Add 1 ml of an 8 pH buffer solution to test tube four. Add 1ml of a 10 pH buffer solution to test tube five. Observe and measure the thickness of foam.

Results Section Two: Substance Sand Water MnO2 Liver extract

Thickness of Foam Layer (mm) 0 mm 0 mm 0 mm 5 mm

The sand, water and MnO2 had no foam layer. The liver extract was the only substance to have a foam layer with a thickness of 5mm. Section Three: Extract Apple Potato Beef steak liver

Thickness of Foam Layer (mm) 0 mm 0 mm 10 mm 20 mm

The apple and potato extract did not have a foam layer. However the beef steak had a thickness of 10mm and the liver extract had a more substantial thickness that was 20mm.

Section Four: Temperature (C) 0 20 37 100

Thickness of Foam Layer (mm) 1 mm 4 mm 7 mm 0 mm

The thickness of foam at 0C was 1mm. The thickness increased at 20C with 4mm. The thickness reached its peak at 7mm at 37C. When we drastically increased the temperature to 100C, the thickness dropped to 0mm. Section Five: pH 2 4 6 8 10

Thickness of Foam Layer (mm) 0 mm 10 mm 30 mm 40 mm 50 mm

When the pH was ta 2, the thickness was 0mm. When the pH was 4, the thickness increased to 10mm. When the pH was 6, the thickness increased to 30mm. When the pH was 8, the thickness increased to 40mm. When the pH was 10, the thickness was 50mm. Each time the pH was raised, the thickness increased by at least 10mm. The pH 10 was the optimum pH for the experiment. Discussion Section Two: All of the substances with the exception of the liver extract did not have a foam layer. The liver extract had a foam layer with a thickness of 5mm. The foam layer is an indicator of hydrogen peroxide breakdown. The foam layer indicates that the solution has an enzyme capable of breaking down the hydrogen peroxide. Water, sand and MnO2 do not have this enzyme but the liver extract does. Although this information was obtained during the experiment, it is not impossible that human error could have played a role in our results. One of us could have added too much water to the test tubes or too much hydrogen peroxide; we could have not added enough of these substances thus altering the results.

Section Three: The plant cell extracts, apple and potato, did not form a foam layer; they showed no sign of catalase activity. However, the animal cell extracts, beef steak and liver, did form a foam layer. The beef steak had a thickness of 10mm and the liver had a larger thickness of 20mm. They both showed signs of catalase activity when the hydrogen peroxide was added to the solutions. Our hypothesis that all cells equally break down hydrogen peroxide was incorrect. The plant cells did not contain the enzyme to break it down while the animal cells did have the enzyme, especially the liver. The liver is known for its digestive nature and is the best candidate to break down the hydrogen peroxide. Our belief that the plant cell extracts would digest the solution was wrong; this was unexpected. Human error could also be playing a role here as we did not get our expected outcome. We could have miscalculated the amounts of each solution to add to each test tube or not collected enough tissue in order to have a proper extract. All of these factors could have affected the results.

Section Four: The optimum temperature for catalase activity was 37C with a foam thickness of 7mm. The temperature of 100C completely inactivated catalase. This happened because when the temperature got too hot, it altered the structure of the enzyme, hindering it from performing its tasks; the enzyme was denatured. This was to be expected because of an enzyme’s known behavior to lose functionality when reaching such temperatures. This disproved our hypothesis that temperature has no effect on catalase activity because all temperatures with the exception of 100C had some kind of catalase activity. Section Five: In this experiment we hypothesized that a higher pH added to catalase in liver cells will increase the thickness of foam thus resulting in higher enzyme activity. Our

results match our hypothesis because our test tube containing the substance with a pH of two had no enzyme activity and the test tube with the substance containing a pH of ten had the most enzyme activity with a foam layer thickness of 50mm; this was the optimum pH. Every time the pH was increased, the enzyme activity was increased. However, if an enzyme functions in the stomach, I would expect the optimum pH to be more acidic in order to be able to function in the stomach’s acidity. When the enzyme changes in pH, the enzyme is altered; this can affect it functionality and structure.

Literature Cited I only referenced the lab report packet that was given....