|Tay-Bug's Biology Blog||
Lactase is an enzyme that breaks down the substrate of lactose. The lactose is broken down into glucose and galactose. Once its broken down its easy to use a glucose test strip to see how much glucose is in the lactose to see how much the enzyme broke down the substrate. For lactase we used a lactase tablet, lactase tablets are normally made for people that are lactose and tolerance because there bodies can’t break don’t have the enzyme lactase. For the lactose we used milk. In this experiment the lactase tablet should be dissolved into water. This is important to do because if you just pore the crushed up tablet into the milk it could clump up on the surface or just clump up in the milk and not get distributed evenly. When you dissolve the tablet in the water and then put it into the milk the tablet is already distributed evenly and it can mix easier into the milk. The purpose for this experiment is to see how temperature effects the reaction rate between the enzyme lactase and the substrate lactose. To achieve this purpose we will have each test tube of milk and the lactase tablet solution set at a different temperature. My hypothesis for this experiment is that the test tube with the highest temperature will have the most reactions will occur and therefore it will have the most glucose in it.
~ 3 Beakers ~ Milk
~ 4 Test Tubes ~ Temperature Probe
~ 1 Ice Bath ~ Mortar and Pestle
~ 4 Crushed Lactase Tablets ~ Tape
~ 2 Hot Plates ~ Glucose Test Strips
The very first thing you do is make the ice bath and start heating up the hot plates, one at 37 degrees Celsius and the other at 98 degrees Celsius. Next fill each beaker with water, sit two on the hot plates and leave the other one on the table. Now its time for measuring, measure out 10ml. of water to dissolve each lactase tablet in something other than the test tube. Then measure out 10ml. of milk into the test tubes. Once all of this is done pore the water and lactase solution into the test tubes of milk. Put the test tubes in the beakers and don't forget to put one test tube in the ice bath. Here is when the tape comes in handy, use the tape to keep the test tubes sitting straight up. It doesn’t matter how you tape the test tube. The next thing is to weight five minutes and then remove the test tubes from the beakers and sit them in a test tube stand. Now get the glucose strips and just dip them in the milk quickly. Let the strips sit for thirty seconds and then look at the color. Use the bottle to compare the colors to tell how much glucose is in each tube.
In the experiment we observed that even with the different temperatures each test tube had the same amount of glucose in it. Its hard to observe the reaction of the enzyme breaking up the substrate but with the glucose strips it allowed us to measure how many substrates were broken up.
From the results of our experiment I can conclude that something went wrong in our experiment, there should have been different amounts of glucose in the test tubes. Looking at other experiments that were done based on the same as ours my hypothesis was correct. There were plenty of errors in this experiment. Since we pored the lactase solution into the milk and then put the test tubes into the different temperatures of water, there is a chance that lactase had already begun breaking down the lactose. We could fix that by putting the test tube of milk into the different temperature of water, let that heat up, and then pore the lactase solution into the milk. Another thing is the tablets were old, some broke up in finer pieces than the others.