Macromolecules Lab Report

The purpose of this lab was to test different substances using various procedures to see what biomolecules were present and ultimately find out what restaurant Anna Lyza had eaten at before she died. For the first control test, we used vegetable oil to test for lipids. So, if the solution does not contain lipids, it does not become translucent when placed onto a paper bag square and held up to a light. So, it is a negative result. However, in the presence of lipids, the solution will become translucent when placed onto a paper bag square and held up to a light. Therefore in this case, the result is positive. On the other hand, we used albumin egg to test for proteins in another control test. If the solution does not contain proteins, it will not experience any color change and so it is a negative result. When there are proteins existing in the solution, it will turn bluish/purplish and for this reason it is a positive result. Furthermore in the third control test, we used dextrose to test for simple carbohydrates such as glucose. If the solution does not contain simple carbohydrates, it will not undergo any color change and will remain a blue color. So, it is a negative result in this circumstance. If there are simple carbohydrates present in the solution, the solution will turn reddish and so the result is positive. For the last control test, we used starch solution to test

All living things contain some form of organic macromolecules including: Lipids, proteins, carbohydrates and nucleic acids. All of these organic molecules are alike in the sense that is they are made up of bonded elements such as carbon, hydrogen, oxygen, and to smaller quantities nitrogen, phosphorus and sulfur. The macromolecules each contain large long chains of carbon and hydrogen atoms and often consists of repeating smaller molecules bonded together in a repeating pattern (polymers). To test whether a specific solid white substance is a protein is simple due to the unique chains found in the respective type of macromolecule. To test if the substance is a carbohydrate, two tests could be performed on separate samples of the object. First,

0.0375 mg/ml Porcine Pancreatic Amylase Solution (amylase powder in 0.9% NaCl ), Iodine Solution; each solution were pipetted into each of the 5 test tubes with 5 ml of 1% starch. Each tube contained a 1% starch solution with a different pH. All tubes were at room temperature. Room temperature was 22C. 0.2 ml of porcine pancreatic amylase solution was then pipetted into each tube. A timer was started and every 3minutes the starch / amylase mixture were pipetted from each tube and pipetted into the spot plate for every sample tube, then the iodine solution were added to a spot plate cell for each sample. Iodine reacts with starch to change from yellow to deep blue /black in the presence of starch. A lightening of the blue/ black to a brown color will occur as less starch is present. Results were reported as (+) for presence of starch in the sample or (–) for the absence of starch. After every three minute increment had passed, these same

The iodine test is used to identify glycogen and starch. These polysaccharides combine with iodine to

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

3. State the name and structure of the functional group for each type of biologically

Dehydration-synthesis is a reaction that occurs to form different types of macromolecules. It is a reaction that leaves a macromolecule structure along the lines of developing its own specific function in a living organism. The 4 most common ones are carbohydrates which includes monosaccharides and polysaccharides, lipids, proteins and nucleic acids (Mack 2012). Scientists identify different types of macromolecules to achieve a better understanding on how they function in our bodies. This can be achieved by studying their chemical properties and structure.

Test tube 1 and 2 didn’t show any color change. These two test tubes had lower levels of pH. Therefore, the enzymes could not change the starch to sugar.

The objective of the Reducing Sugar Test was to test if the substance has a reducing sugar in it by adding Benedict’s solution and heating it, there would be a color change if a reducing sugar is present, or it will remain blue (no reducing sugar). The objective of the Starch test was to test for starch in substances by using Iodine. The iodine will cause a substance to turn to a dark blue color if it is positive for starch. The objective for the Grease Spot Test was to test if the substance had a lipid. A positive reaction would make a translucent grease mark on a brown paper bag. The objective for the Dye test was to test for lipids. When mixed with water and the tested

1. Carbohydrates: Are Molecule composed of carbon, hydrogen, and oxygen, and they include sugars and starches.

For this experiment, we have to prepare our phosphorylase which extracted from a potato. We prepared by weighed about 250 grams of peeled potato and cut it into cubes. The extracts then blended with 100mL of 0.1M NaF. After filtered the contents into a clean 250mL centrifuge bottle, we centrifuged it for 3 minutes. Then, separated the supernatant into a centrifuge bottle, which is our phosphorylase preparation. The enzyme assay used in this experiment today is the iodine test. As the iodine reacts with starch, it will form a brown, blue or black precipitate due to the iodine ions forcing into a linear arrangement. The endpoint of the enzyme reaction indicates the presence of starch by using the iodine test to determine. The faster the endpoint is reached, the less active the phosphorylase is.

The macromolecule protein is made up of monomers called amino acids which are nitrogen-containing molecules (Hoffman and Falvo, 2004). These amino acids are joined together by peptide bonds. Amino acids can be categorized into three types called essential amino acids, semi-essential amino acids and non-essential amino acids. Essential amino acids (e.g.: valine and phenylalanine) refer to amino acids that are not synthesized in the human body; hence it has to be provided in the diet. Semi- essential amino acids represent amino acids that are synthesized in the body but not in adequate amounts; therefore it has to be supplied by the diet in small amounts. Non- essential amino acids (e.g.: alanine and glycine) are synthesized by the body and

Tofu White/Brown Blue Negative Methods Iodine test for the starch in food items, so in order to test the starch in our food products, we marked our test tubes at 1cm and added grinded food sample to 1cm mark and used droppers to put 10 drops of Iodine solution in the test tube to observe the color change in our samples to get positive or negative result. Results: Iodine Sample name Original color Final color Positive/Negative Potato Dark Black Black Positive Fried Noodles Black Black Positive Egg Light orange or yellow Yellow Negative Tofu White/brown Black/Purple Positive

This allowed for the testing of certain particles by the use of indicator chemicals. Stock solution was placed in three other test tubes. The cup water served as the experimental variable, and the stock solution served as the control variable (1). Iodine serves as an indicator chemical for starch in this experiment. When added to a starchy solution, iodine will change colors. Usually iodine will turn from an amber color to very dark or black color if starch is present, and if not, it will remain amber. A dropper full of iodine was placed in two test tubes: one filled with the stock solution, and one filled with the cup water (1). Silver Nitrate was used in this experiment to determine whether or not salt was present in a solution. As a chemical indicator, silver nitrate detects the presence of chloride ions (salt contains chloride ions and sodium ions). The solution will change color from clear to cloudy if salt is present. A dropper full of silver nitrate was placed into two test tubes: one filled with stock solution, and one with the cup water (1). Benedict’s solution was used in this experiment as a chemical indicator to test for the presence of simple sugars. If glucose (sugar) is present, the solution will change color. Starting out blue, Benedict’s solution will change to green, yellow, orange, or red,

Solutions and color reaction for Benedict’s test for reducing sugars and 2 iodine test for starch