Experiment 1: Testing for Proteins The protein molecules in many foods provide the amino acid building blocks required by our own cells to produce new proteins. To determine whether a sample contains protein, a reagent called Biuret solution is used. Biuret solution contains copper ions. However, the chemical state of the copper ions in Biuret solution causes them to form a chemical complex with the peptide bonds between amino acids (when present), changing the color of the solution. Biuret solution is normally blue, but changes to pink when short peptides are present and to violet when long polypeptides are present. Figure 6: Biuret solution only is located on the far left side of the image (blue). Note the transition from blue to …show more content…
Swirl each tube to mix. 8. Record the final color in Table 1. Note: Protein is present in the sample if a light purple color is observed. Table 1: Testing for Proteins Results Sample Initial Color Final Color Protein Present 1 - Albumin Solution 2 - Gelatin Solution 3 - Glucose 4 - Water 5 - Unknown Post-Lab Questions 1. Record your hypothesis about what will happen when Biuret solution is mixed with the solutions from test tubes 1, 2, 3, and 4 here. Be sure to use scientific reasoning to support your hypothesis. 2. Write a statement to explain the molecular composition of the unknown solution based on the results obtained during testing with the Biuret solution and each sample solution. 3. Diet and nutrition are closely linked to the study of biomolecules. How should you monitor your food intake to insure the cells in your body have the materials necessary to function? 4. There are other types of reagents used to determine what type of biomolecule a substance is. For example, copper ions present in Benedict’s reagent reacts with the free end of any reducing sugars, such as glucose, when heated. Originally blue in color, these copper ions are reduced by the sugar, and produce an orange-red colored precipitate. Alternatively, iodine-potassium iodide (IKI) may also be used when working with starch. IKI contains special tri-iodine ions which interact with the coiled structure of a starch
The purpose of this lab was to determine the limiting reactant in a mixture of to soluble salts and the percent composition of each substance in a salt mixture.
3. Experiment: Use the Gizmo to find the carrying capacity with Ample, Moderate, and Little land. List the carrying capacities below.
Typically an ionic bond occurs between one metal and one non-metal ion. One atom borrows one or more electrons from another atom. An ionic bond is a type of chemical bond that occurs when one atom loses an electron to form a positive ion and the other atom gains an electron to form a negative ion, which then result in attraction.
The materials used for this experiment were, distilled water, albumin, pepsin, and starch. The liquids used to identify these organic molecules were Biuret reagent, Benedict’s reagent, and iodine solution. Biuret reagent is a blue colored liquid that identifies proteins or peptides in a solution. Benedict’s
What observations can you make regarding the gene pool and gene frequency of the surviving individuals?
Testing for the presence of starches in the unknown solution with Lugol’s reagent will be referred to as Test 3
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
a. Change the 24th bead to a different color. What does the sentence say now (re-read the entire sentence)? Does the sentence still make sense?
Based on the results of your experiment, would you reject or accept each hypothesis that you produced in question 1? Explain how you determined this.
7)a) You would do the Benedict’s reagent test for simple sugars and the Lugol’s solution or Iodine test for polysaccharides and starch. To test the lipids you would use the Sudan iV test and Biurets reagent test for protein.
Develop a hypothesis relating to the amount of dissolved oxygen measured in the water sample and the number of fish observed in the body of water.
groups. It was conducted to further the research in choice overload and paralysis of the mind.
Draw conclusions – Assuming that your experiment produced results identical to those seen in Table 4, would you reject or accept the hypothesis that you produced in question 3? Explain how you determined this.
Gel electrophoresis method. Qualitative analysis shows protein concentrations in kidney, heart, and liver. 1-6 are kidney tissue. 7-14 are liver and 15-19 are the heart tissue.
enzymes that will be used during this lab to test the ability of amylase to break down starch ,a