Enzymes are proteins that act as catalysts; thus allowing the many chemical reactions in life to occur. The purpose of an enzyme is to speed up the rate of a chemical reaction. Without enzymes, living organisms would be unable to function properly, since the releasing and storing of energy depend on the enzyme’s function (2). Through the process of catabolism, complex molecules within organic compounds are broken into simpler molecules. As a result of catabolic reactions, energy used to produce chemical reactions is released. In contrast, anabolic reactions store energy by the formation of complex molecules from simpler ones.
However, both energy managing reactions depend on ATP produced by enzymes, otherwise known as chemical energy (2). When a substrate is temporarily bonded to an enzyme, enzymatic reactions occur. In an enzymatic reaction, a specific substrate tailored to an enzyme is bonded at the active site, where the enzyme acts upon the substrate and releases a product (1). Despite enzymes only acting upon distinct substrates, factors such as denaturation and inhibition can prevent enzymatic reactions from occurring. In this lab, samples of pineapple and jello were observed to determine the function of enzymes.
If a canned and fresh pineapple chunk were placed on separate petri dishes with jello, then the state of the jello would be similar because both pineapple samples contain bromelain, a protein digesting enzyme. Jello consists of collagen, which can be found in animal bones and tendons, therefore classifying jello as a protein. By maintaining contact between the pineapple and the jello, the hypothesis was tested through creating an enzymatic reaction. This study concluded that while a natural enzyme is able to act on a substrate and release a product, denaturing of an enzyme hemically alters the enzyme and its ability to react with a substrate.
Materials and Methods A chunk of fresh and canned pineapple were selected as independent variables for this experiment. Each pineapple sample was placed in separate petri dishes containing jello. Observations of the physical characteristics and state of the jello were noted. The petri dishes were covered by a lid and left alone for a span of twenty-five minutes. Differences in the appearance of the jello were observed after twenty-five minutes and once again after twenty-four hours.
All data collected was recorded in a table. Results Reactant Jello with Canned Pineapple Jello with Fresh Pineapple Before Reaction solid jello (red), separated pineapple (yellow) and jello, slight coloring on base of pineapple solid jello, still in distinct forms After 25 minutes solid jello, separated jello and pineapple, more coloring on base of pineapple solid jello, separated jello and pineapple, slight coloring on base of pineapple After 24 hours jello is chunky, not liquefied, and preserves its shape liquefied jello
Both the canned and fresh pineapple samples contained the enzyme, bromelain, but had different reactions on the protein substrate. Although not much of a difference was observed after twenty-five minutes, a span of twenty-four hours distinguished the ability of a normal and denatured enzyme to act on the jello. The fresh pineapple chunk digested the proteins within the jello, which produced liquid jello as a result of the reaction. The canned pineapple underwent a chemical change when processed, thus denaturing the enzyme and resulting in the jello remaining solid.
Being that the fresh pineapple’s bromelain was unaltered, it was able to react the best with protein within the jello. Discussion The function of enzymes are altered when under different circumstances. Although both pineapple samples contained bromelain, the bromelain within the canned pineapple was denatured. Denaturing an enzyme chemically alters the active site, meaning the enzyme no longer has the ability to bond with and act upon a substrate. As a result, the jello contacting the canned pineapple retained its shape and composition.
Thus, the hypothesis stating that both pineapple samples will react similarly with the jello, is proven false. In this experiment the variables were the state of the jello after the reaction and the types of pineapple; canned and fresh. The state of jello depends on the bromelain within the pineapple, therefore classifying the state of the jello as the dependent variable and the independent variable is the pineapple. Controls that were used in the lab were the types of jello, amount of jello, amount of pineapple, size of petri dish, and the amount of time by which the pineapple chunks are placed on the jello.
When jello was in contact with the canned pineapple, no reaction occurred after twenty-four. Only the bromelain within the fresh pineapple was able to digest the proteins in the jello. Conclusion The enzyme lab determined the function of enzymes on substrates, using pineapple and jello. The experimenter placed a chunk of fresh and canned pineapple on two separate petri dishes with jello. Observations of the reactions were recorded after twenty-five minutes and twenty-four hours. The experiment was done to test the function of enzymes on substrates and when the enzyme is denatured.
The results did not support the hypothesis because despite both types of pineapple containing bromelain, the bromelain within the canned pineapple was denatured. The fresh pineapple chunk digested and liquified the jello, while the canned pineapple chunk left the jello chunky and solid. It was learned that denaturing an enzyme causes it to have little to no function. Outside factors, such as heat, chemically alters the enzyme; thus limiting its ability to act on a substrate. The normal enzyme was able to digest the proteins within the jello and release a product (liquid jello).
