In this experiment starch and glucose is tested to see if it can pass through visking tubing. The set up is as shown below:
The visking tubing has very tiny holes in it to allow certain types of molecules to pass through. A starch test and sugar test is conducted at the end of the experiment to test for presence of starch and reducing sugar in the distilled water.
The set up was left for 20 minutes and the distilled water in the boiling tube was poured evenly into 2 test tubes.
Starch Test
For the first test tube a few drops of iodine solution was added into the test tube to test for presence of starch, since iodine solution will turn from yellowish brown to blue black when it comes in contact with starch.
In the experiment, the distilled water did NOT turn from yellowish brown to blue black. This shows that the starch was unable to pass through the visking tubing.
Reducing Sugar Test
A few drops of Benedict’s solution (consists of Copper sulfate, Sodium citrate and Sodium carbonate) was added to the second test tube to test for presence of reducing sugars, in this case glucose. The benedict’s solution will turn from colourless to yellow, green or red (depending on the amount of reducing sugar present) if reducing sugars are present.
This is our group’s experiment and it was successful:
This experiment is just like the small intestines in our body. As food gets digested, certain molecules will pass through the walls of the small intestines and get into the bloodstream, while other molecules do not.
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