Enzyme Lab

If temperature of the water(enzyme environment) is increased to 35°C, then the enzyme activity will

All hypotheses predicted were correct for all factors tested according to the appropriate justification, except for one hypothesis in Part C. In Part A the increased number of enzyme concentration (also known as beef liver catalase) increases the rate of the reaction increases as well so long as all other factors such as pH, ionic concentrations and temperature remain unchanged or fixed. Furthermore, if diluted concentrations of 1.5 % and 3% the substrate concentration increases and the rate of the reaction until it reaches a limiting factor and becomes fully saturated. However, if simply distilled water without hydrogen peroxide is utilized the hydrogen peroxide would decrease as the rate of the reaction because no substrate enzyme complex will be formed therefore creating no products. Lastly, increasing the concentration of heavy metal ions, such as copper (II) Sulphate and lead (II) nitrate, will decrease the rate of the reaction as it will disrupt the bonds between the amino acids of the proteins denaturing the enzyme structure and function. It was learned that if distilled water is used without the concentrations of copper(II) Sulphate and lead (II) nitrate the rate of the reaction decreased as the heavy metal salts decreased. As a result of more water molecules, there is no substrate or enzyme catalase the reaction and quickly form a

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;

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pH levels are a factor, as most enzymes work in a alkaline environment ( Human body is alkaline based).

If a salt concentration is too high or low, enzyme activity will happen overly slow (if at all) or excessively fast. None of the concentrations used during this experiment were high enough to shift the shape on an enzyme’s active site, or denature a protein. Of the four concentrations used in this experiment, 10% and 20% salt concentration have the smoothest curves and lowest absorbance. This leads us to believe that of the four different concentrations, 10 and 20% concentrations are optimal for enzyme activity compared to the lower concentrations. We reject the null hypothesis, because the higher salt concentrations are, the slower the rate of an enzyme reaction will become.

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).

An enzyme is a protein macromolecule which acts as a catalyst, an agent which speeds up reactions without being consumed by it. They are vital to life; cellular chemical reactions would not occur fast enough to support life, without the aid of enzymes. They do this by lowering the activation energy (EA), which is the energy that must be added to the reactants at the start of reactions, it has to be reached in order for the reaction to occur (Reece, Wasserman and Urry). There are hundreds of enzymes known, but not all cells contain the same ones, an example of this is catalase which will be the experimental enzyme in the lab.

pH - Enzymes also have an optimum pH level. The pH of a solution affects the enzyme's secondary and tertiary structures. These bonds make the shape of an enzyme's active site. So, if these bonds are broken, the shape of the active site changes and is distorted. If there is no active site, there is no reaction resulting in no products. If the enzyme is put in a pH that is very different from the optimum pH, it can cause the enzyme to denature.

The purpose of this lab is to test for enzyme activity by examining factors that may influence enzymes.

The purpose of this investigation is to discover the effect of pH on the activity of catalase, an enzyme which plays the integral role of converting hydrogen peroxide into water and oxygen, and discover which pH level it will work at the most efficient rate (the optimum). The original hypothesis states that that the optimum would be at a pH is 7, due to the liver, where catalase usually resides, being neutral. The experiment consists of introducing the catalase to hydrogen peroxide, after exposure to certain solutions; hydrogen peroxide, water and hydrochloric acids, all containing the adjusted pH, and measuring the height of froth formed, an observable representation of the activity of the enzyme. The final data indicated that

“Enzymes are proteins that have catalytic functions” [1], “that speed up or slow down reactions”[2], “indispensable to maintenance and activity of life”[1]. They are each very specific, and will only work when a particular substrate fits in their active site. An active site is “a region on the surface of an enzyme where the substrate binds, and where the reaction occurs”[2].

Organisms cannot depend solely on spontaneous reactions for the production of materials because they occur slowly and are not responsive to the organism's needs (Martineau, Dean, et al, Laboratory Manual, 43). In order to speed up the reaction process, cells use enzymes as biological catalysts. Enzymes are able to speed up the reaction through lowering activation energy. Additionally, enzymes facilitate reactions without being consumed (manual,43). Each enzyme acts on a specific molecule or set of molecules referred to as the enzyme's substrate and the results of this reaction are called products (manual 43). As a result, enzymes promote a reaction so that substrates are converted into products on a faster pace (manual 43). Most enzymes are proteins whose structure is determined by its sequence of its amino acids. Enzymes are designed to function the best under physiological conditions of PH and temperature. Any change of these variables that change the conformation of the enzyme will destroy or enhance enzyme activity(manual, 43).

Hold the IKI spray bottle 25 - 30 cm away from the paper towel, and mist with the IKI solution.

In the experiment we used Turnip, Hydrogen Peroxide, Distilled Water, and Guaiacol as my substances. On the first activity, Effect of Enzyme concentration of Reaction Rate for low enzyme concentration, we tested three concentrations of the turnip extract, and hydrogen peroxide. For the Turnip Extract I used 0.5 ml, 1.0 ml, and 2.0 ml. For hydrogen peroxide we used 0.1 ml, 0.2 ml, and 0.4 ml. We used a control to see the standard, and used a control for each enzyme concentration used. The control contains turnip extract and the color reagent, Guaiacol. We prepared my substrate tubes separately from the enzyme tubes. My substrate tube