Biological Molecules Lab Report

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 following tests according to the lab manual were performed: gram stain, fermentation tubes, methyl red, vogues proskauer, sulfur, indole, motility and growing it up on MacConkey agar. The gram stain was performed incorrectly the first time. This is because the decolorizer was not on the bacterium slide for long enough, giving a false outcome.

Different reagents were used for the tests with the reagents reacting with the molecules in a specific way indicated by a change of color. Controls were provided to ensure integrity of the process. The results indicated the presence or absence of the organic molecules in the various substances provided. They proved that using these tests, one can accurately determine what organic molecules a substance contains. This will help in determining the composition of various substances within the cell or even outside the body and how they affect normal cell

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

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

I began by running the starch test, which tests for the presence of starch hydrolyzing enzymes. After doing a one-line inoculation of the organism, the plate had to be incubated. Once I received an appropriate amount of growth I added the reagent iodine. The iodine turned the plate purple, formed no clear zone, and lifted the organism off of the plate, which revealed that the starch was not degraded and the enzyme was not present. The organism being lifted off the plate is unique to the bacteria Corynebacterium xerosis indicating that it was my gram positive rod. For reassurance, I ran the Phenol Red Glucose test, which tests if the organism contains various enzymes that determine if the bacteria can ferment glucose. After incubation, the broth turned orange, but this did not provide a clear positive or negative result so I ran the Nitrate Broth Reduction test. The Nitrate Broth Reduction test detects if the organism utilizes nitrate. After incubation for forty-eight hours I added Nitrate A and Nitrate B indicators. However, there was no color change indicating that the test was inconclusive. Since the test was inconclusive, I proceeded to the following step, which included adding a small amount of zinc to the broth, and this turned the broth a red color. The red color indicated that

2. Four unknown samples were included in the lab kit: flax seed meal, potato starch, egg whites, and dried milk. Using the results of the biochemical testing, determine which number corresponds to the correct unknown. (8 points)

b) Benedict test the solution color will change from blue to pink/orange red, indicating simple sugars are present. Lugols test the solution color will change from yellowish brown to dark purple, indicating starch and polysaccharides are present. Sudan iV test the lipid content will turn into red, indicating lipids are

An association between enzyme production, gene copy number, and gene evolution was explored by conducting analysis of the salivary amylase enzyme, AMY1A gene copy number, and the ancestral starch consumption in Homo Sapiens (Tracey 2017, p.22). It was hypothesized that the relative amount of starch consumption was very high for my personal ancestral diet, thus my AMY1 diploid gene copy number in my genome and salivary amylase concentration would be significantly higher than the population mean. With a population of 28 subjects (n=28), individual saliva samples were collected and compared to a calibration curve to determine the approximate amylase concentration by analyzing absorbance values. Individual samples of buccal cheek cells were

Procedure: Filled each test tube with substances provided and subjected them to various conditions. These conditions included, heat, cold water, hot water, acid and basic additions and tested on litmus paper. The reactions were observed and documented at each step.

2. (5 pts) List and explain the names and affiliations of the various characters/stakeholders in this story – I’m looking for us to use the story to map out the complexities that are generally associated with solving public health puzzles – the stakeholders you list and explain here should apply to many of the cases we consider going forward.

Dispense .5 mL water into the already weighed conical vial, replace cap and face insert on its down side.

We saw that the 10 drops of cracker solution didn’t have any glucose in it because the solution was the same colors as the control solution after we added the Benedicts solutions. But after we added Benedict's solution to the solution containing 10 drops of the cracker solution and the amylase we saw a color change that differed from the control, we saw the cracker solution and amylase turn green which shows that there was glucose in the solution. Compared to the control and the test tube with the cracker solution which were a light

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

During the Benedict's test, the contents of tube B did not change, indicating the absence of sugar in that particular substance. However, the contents of tube A did change orange indicating the presence of sugar in that substance. During the Lugol's test, the content of tube A did not change dark purple indicating the absence of starch in that substance However, the content of tube B changed to dark purple