Exercise 3 Biology Answers

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

Used to see if the temperature of the water is at 37oc – 40oc and if

Amylase experiment # 2 was done to see how the pH affected the efficacy of the enzyme. First we collected all of the materials that were necessary to make this experiment. We needed five clean test tubes, the following standard solutions, 1% Starch Solution pH 3,1% Starch Solution pH 5,1% Starch Solution pH 7,1% Starch Solution pH 9,1% Starch Solution pH 11

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)

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)

An enzyme also known as a protein, is a biological catalyst which speeds up chemical reactions by lowering the activation energy to increase the rate in which the reaction occurs. The enzyme used was amylase, which breaks down starch molecules into maltose. PH, substrate concentration, salt concentration, and temperature. When enzymes reach a low temperature, the activity is slowed down of molecule movement, but the enzyme is not destroyed. Once enzymes are placed in optimal temperatures once again, it will restore its activity to a normal rate. When enzymes reach too high above optimal temperature, the enzyme is denatured and cannot be restored. In the experiment performed the activity of breaking down starch in fungal and bacterial amylase was being tested at a range of temperatures and time. The fungal and bacterial amylase work best at optimal temperature. Amylase will function best at sixty degrees Celsius at 10 minutes when starch had been one hundred percent hydrolyzed. Hydrolyzed is the breakdown of molecules through addition of water. The experiments independent variables were the time, temperature and enzyme used. The dependent variable was the enzyme activity that broke down the starch into maltose. The controlled variables were the temperature baths, the iodine drop amount, the mixture drop amount, and location of experiment. The control group was the zero minutes without amylase at

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

This experiment consisted of setting up a control group of starch in various temperature and then placing both fungal amylases and bacterial amylases in a mixture of starch and placing the solution of amylase and starch in various temperatures of water. After a certain amount of time- different amount of time needs to be used in order to have reliable results- iodine is added in a well on spot plates, then two drops of the mixture of amylase-starch is added from each temperature used, by adding iodine into the plates the mixture will show how much starch was hydrolyzed, this is used to calculate the amount of

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.

Hypothesis: If we decrease the level of pH in the enzyme Amylase, it will not be able to denature the carbohydrates in the potato starch solution after 10 drops because enzymes are very sensitive to pH levels and lowering it too much will compromise its ability to break them down.

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

Amylase is an enzyme that is in human’s saliva as well as the pancreas. Enzymes are biological catalysts that speed up a chemical reaction. They break down complex molecules into simple ones. In this case, amylase converts starches (complex molecule) into simple sugars. That is why foods like potatoes for example, may taste sweet to us, because they contain starch. The optimum pH for pancreatic amylase is the pH of 7. In the experiment I have used buffer solutions with the pHs of 2.8, 4 and 6.5. I have also used iodine and starch. Normally, iodine is orange-yellow, however when you add starch to it, the solution will turn blue-black.