Lab 8 - Chemical and Physical Processes of Digestion

1. Fill in the table below with the results from the monosaccharide test experiment, and your conclusions based on those results.

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

There are many types of enzymes and each has a specific job. Enzymes are particular types of proteins that help to speed up some reactions, such as reactants going to products. One of them is the amylase enzyme. Amylases are found in saliva, and pancreatic secretions of the small intestine. The function of amylase is to break down big molecules of starch into small molecules like glucose; this process is called hydrolysis. Enzymes are very specific; for example, amylase is the only enzyme that will break down starch. It is similar to the theory of the lock

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)

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.

3. We poured tube 1 with the solution in tube 3 to combine them. We repeated this for all of the tubes. Each of the tubes in step 1 was mixed with a tube in step 3, making there be 6 total test tubes with a solution in it.

Which of the foods that you tested contained amylase? Which did not? What experimental evidence supports your claim?

2.List whether each of the following substances was positive or negative for reducing sugar, as indicated by the Benedict's test. (6 points)

enzymes that will be used during this lab to test the ability of amylase to break down starch ,a

In part II of the lab six small glass tubes were obtained in a test tube rack. Ten drops of distilled water were then added to test tube 1, five drops to tubes 2-4, and no drops in tubes 5 and 6. Five drops of 0.1M HCl were added to test tube 5 and five drops of 0.1M NaOH to test tube 6. Five drops of enzyme were then added to all tubes except tube 1. Tube 3 was then placed in the ice bucket and tube 4 was placed in the hot bucket at 80-900C for five minutes, the remaining tubes were left in the test tube rack. After the five minutes five drops of 1% starch was added to every tube and left to sit for ten minutes. After ten minutes five drops of DNSA were then added to all the tubes. All the tubes were then taken and placed in the

test the pH of the amylase a drop of the solution should be put on pH

The purpose of this lab was to understand how different solutions played a role in the digestion protein. By looking at different variables, such as temperature, and pH we’re capable of understanding just how certain substances functioned and when they didn’t. The data for all labs are clear and concise and give a clear understanding of what solutions work best. All three labs were placed in a warm water bath set at 37’C to stimulate the reaction as if it were taking place within the human body. This gives us a more accurate reading on how they would react at that set temperature. We concluded why certain tubes changed to the color they did and further explained it. This lab focuses primarily on two crucial

Digestion is the chemical breakdown of food into smaller components that are more easily absorbed. Digestion is a form of catabolism: a breakdown of large food molecules to smaller ones. When food enters into stomach, gastric juice starts protein digestion. Gastric juice mainly contains hydrochloric acid and pepsin. The pH value of hydrochloric in the stomach is 2, as the activity of pepsin is optimal, while it will lose its activity at pH 6.5 and above. However, pepsin will regain its activity at pH of 8. In the range of pH1 to pH6.5, pepsin will be most active at pH2, and starts to decrease its

Half of each tube’s contents are poured into a new test tube each respectively after the tubes are incubated for 1 hour. One set of tubes is tested for:

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