Metabolism Of Unknown Organisms

This experiment was centered on metabolic and biochemical testing procedures. The rationale of performing these tests was to distinguish six different microbes from one another and to compare how their metabolic and biochemical processes differ from species to species to determine the unknown sample.

PH can affect the way fermentation occurs due to the irregularity of the acidity or alkalinity within the glucose solution. This is an enzyme-based reaction that is susceptible to pH. The aim of this experiment was to determine how pH affects the yeast fermentation rate by performing the experiment numerous times with a different pH of glucose solution which included pH 3, 5, 7, 9, 11. The hypothesis was ‘If the pH is lower than the neutral point then the fermentation reaction will occur faster?’ The experiment conducted was to measure the amount of C02 produced by the yeast going into fermentation, however varying the pH of glucose solution by using different pHs . To test this every 5 minutes the volume of gas in the test tube was observed and recorded until a period of 30 minutes had been. The end results

A cell, the building block of all living organisms, is composed of four fundamental biomolecules: proteins, carbohydrates, sugars and lipids. Proteins provide a vast amount of functions cells such as they serve as enzymes, provide structural support to cells, and act as antibodies. Reagents are used to spark a chemical reaction. The reagent used to detect protein traces in a substance is Biuret’s. Biuret’s will turn purple if proteins are present and blue if they are none. Biuret’s copper particles, have a charge of +2, are diminished to a charge of +1 when peptide bonds, which are in proteins, are present, creating the color change. Polysaccharides, which are carbohydrates, are most notably known to provide energy to the body, but they also help in breaking down fatty acids. Iodine is the reagent used to determine whether a substance has starch in it. The iodine/starch complex has energy levels that are only for retaining unmistakable light, giving the complex its extraordinarily dark black-blue shade. If there is no starch found, iodine will remain its natural yellowish-brownish color, but if starch is present, iodine will turn blue-black. Monosaccharides, which are sugars, like polysaccharides, provide the body with energy. To detect monosaccharides, the reagent, Benedict’s, is used. Benedict’s reagent is added to a test tube, then it is placed in

In biology, we learn a lot of information that we can use later on in life, no matter what field of study we go into. During this course, we learned about biochemistry, metabolic processes, homeostasis, molecular genetics and population dynamics. Throughout the learning process, we’ve had many questions or INTUS, which we use to expand our knowledge later on and determine the answers to those specific questions. The point of this assignment is to relate questions that we have developed on our particular topic we chose; to these five units we studied in biology.

To perform this test, a tube of broth rich with glucose is acquired. In this tube is phenol red, a pH indicator. Initially, the tube appeared pink in color, indicating a normal pH level. Next, a sample of unknown #44 is introduced into this medium using the aseptic technique, and this is allowed to sit for several days. If the organism is able to ferment glucose, the pH in the medium would decrease and cause the phenol red to exhibit a yellow color. In addition to the straw color, gas can also be produced and trapped inside the Durham tube placed in the medium. This production of acid and gas is a direct result of the fermentation of glucose, as seen with unknown

The SIM media contains nutrients, iron, and sodium thiosulfate. Hydrogen sulfide can reduce to sulfur, and if this occurs, then the hydrogen sulfide will produce a black precipitate by combining with iron to make ferrous sulfide. If the broth does not turn black, then the test is negative. Kovac’s reagent was added to the SIM media to test for indole. Tryptophanase is an enzyme that hydrolyses tryptophan. The products from this reaction are indole, pyruvic acid, and ammonia. The Kovac’s reagent that was added should form a red compound in the SIM media to have a positive result. If the media does not turn red then the test is negative. Also, in the motility test, the test tube was stabbed with the unknown, and growth around the stab line would indicate a positive test result. The MR-VP test contains two test and two test tubes. The MR and VP were subcultured in separate test tubes, but the same broth was used for both tests. Adding methyl red (pH indicator) to the broth is the indicator for the MR test. If the bacterium uses mixed acid fermentation pathway and stable acidic products are made, the acids will make an acidic environment. When methyl red is put into the medium, the broth will stay red if there are acidic products present. The VP tests shows bacterium that use the butylenes glycol pathway and have a product of acetoin. The acetoin that is

The same type of experimental process was used in the other experiments of temperature, and enzyme, substrate, and ionic concentration. For example, for temperature, they replaced the distilled water in the cuvettes with water of different temperatures of 3, 15, 25,37,and 100 degrees Celsius. Then, after the colorimeter was calibrated, the absorbance and transmittance of the data was collected for 2 minutes in increments of 20

At the end of 60 minutes, test tube 1 ,2, 3, 4, 5 and 6 produced 47 mm, 33 mm, 4 mm, 4 mm, 9 mm and 46 mm of CO2, respectively. The amount of CO2 produced tells us that there was a high rate of cellular respiration in test tube 1, 2 and 6 and there was a low rate in test tube 3, 4 and 5. As shown on the graph, there is a steeper slope for test tube 1, 2 and 6 and gentle slope for test tube 3, 4, and 5. The steeper the slope the faster the rate of CO2 produced. The test tubes 1, 2 and 6 had high rate of respiration because of the presence of glucose, maltose and MgSO4, respectively. Both glucose and maltose is able to give more amount of CO2 than any other substrate. MgSO4 is a cofactor and the presence of the cofactor allows better formation of pyruvates resulting in a higher rate of cellular respiration. The test tube 4 had a low rate because it contained no substrate for respiration, there was only water. There was a low rate in test tube 5 because of the presence of NaF. NaF is an inhibitor and have the capacity to interfere with the enzymatic activity. The presence of alanine will result in low rate of cellular respiration as seen on test tube 3 because alanine has least amount of carbon in

The oxidation fermentation test was used to differentiate if the organism utilizes lactose, mannitol, glucose and citrate aerobically (oxidation) or anaerobically (fermentation). A methyl red test was performed to determine if the organism carried out mixed-acid fermentation when supplied glucose. A Voges-Proskauer test was performed to evaluate if the unknown was able to ferment glucose into butanediol. A citrate test was performed to determine if the unknown organism was able to break down citrate into ammonia. An oxidase test was then performed to determine if the unknown culture was oxidase positive or negate.

For example using media that contains a certain sugar, like glucose, will show if the organism can use that sugar in the absence of oxygen to produce acid. As well as preforming a catalase test that will show the bacteria’s ability to produce catalase when hydrogen peroxide is added to the microorganism. If the organism is positive for catalase it will demonstrate bubbling after the hydrogen peroxide is added, which means that the organism can produce the enzyme catalase to breakdown hydrogen peroxide to water and oxygen gas. Cell wall structure also varies in microbes, preforming a gram stain can help narrow down the identity of the microorganism by classifying it as gram-positive (+) or gram-negative (-). These among other similar identification techniques can help determine an unknown bacteria in a mixed

Abstract: In this procedure, phenolphthalein will be used to detect changes in pH resulting from the production of CO2 during cellular respiration. Because phenolphthalein is red in basic solutions and colorless in acidic solutions, you can monitor cellular respiration by measuring acid production as change in pH. CO2 produced during cellular respiration can combine with water to form carbonic acid. By measuring the volume of NaOH used to neutralize the carbonic acid produced by the CO2, and thereby calculate a proximate measure of respiration.

Abstract: Metabolism is used to refer to all of the chemical reactions involving energy transformations in the cell of the body, for example cellular activity such as cellular respiration and its sub activtys like glycolysis, Krebs Cycle and the Electron Transport Chain all produce energy in the form of ATP and a byproduct of the energy production, heat is also produced . Although the cell is not 100% efficient thermodynamically, the energy in the form of heat is lost in the cell each time when energy is produced. Metabolic rates of an organism can be measured directly by the amount of heat lost from the body in a certain period of time. Another way an organisms metabolic rate can be measured is indirectly, by measuring the amount of oxygen that is consumed in a given period of time. In the experiment conducted, we needed to find the metabolic rate of an ectotherm. Using a goldfish (ectotherm) we calculated the metabolic rate by means of counting the number of operculum beats when three different goldfish where submerged in various temperatures. What was found is that the metabolic rate increased when the temperature increased and the metabolic rate decreased as temperature dropped.

In the first part of the experiment, the goal is to observe the metabolic and fermentation rates of yeast. The class worked together to determine the specific measurements of gas that was produced over time using the fermentation tubes. During the second portion of this lab, Cellular Respiration was observed in a redox reaction converting succinate into fumarate. Di-chlorophenol, also known as DPIP was used to represent an electron acceptor that collects the Hydrogen ions released by the redox reaction. This redox reaction is what is used for The Citric Acid Cycle to continue the aerobic respiration cycle.

The Cycle of Cellular Respiration and Fermentation Introduction: In this Cellular Respiration and Fermentation lab, we discuss about the cellular respiration which is classified as an aerobic process and fermentation which is anaerobic process. An aerobic process is where it contains oxygen unlike the anaerobic process does not. In the aerobic process there are 4 steps that should be recognized: glycolysis, conversion, citric acid cycle, and the electron transport chain. This experiment contains or uses the yeast concentration to see how much CO2 developed over 20 minutes, counting per 2 minutes and measuring how much has progressed.

Name ____________________________ I) Introduction All cells contain four major types of macromolecules: carbohydrates, lipids, nucleic acids, and proteins. In today’s lab, we will be studying three of the four-proteins, carbohydrates and lipids. Various chemical tests can be used to detect the presence of each of these molecules. Most of the tests involve a color change visible to the eye. If a color change is observed, the test is considered positive. If the color change is not observed, the test is negative, indicating that a particular molecule is not present. In all the chemical tests we will be performing, we will also be using a control. In most cases, the control will be a sample of