Biology 124L Sec. 142
In the experiment the class used five different macromolecules such as instant soup, flour, fruit juice, milk and dessert gelatin to test the physical and chemical properties when mixed with positive and negative controls. In groups, we used four experiments consisting of Starch, Benedict’s, Sudan IV, and the Buiret test. As a class we came up with a hypothesis for my group stating, “Dessert gelatin contains sugar and starch and does not contain starch and protein.” This is because we figured that being a dessert it should already contain sugar, but when making gelatin it starts out as a liquid and when cooled it turns into a solid. When it’s officially a solid it will not dissolve back into a liquid. So having this, it leads to the prediction, “Dessert gelatin will test positive for Benedict’s and Sudan IV tests and negative for the Start and the Buiret tests. Using this prediction we were able to test our hypothesis and decide whether we started in the wrong direction.
The lab was broken up into four test groups starting with the Benedict’s test. The Benedict’s test is a positive for sugar. Three test tubes were used: one with the Benedict’s solution and water as the control and the other with glucose and Benedict’s solution. After the test tubes were done, they were put in boiling water and set for 10 minutes. The color of the positive control was dark blue, the color of the negative control was clear and our final result was dark blue meaning it was positive for sugar.
|Color of + |Color of - |Final Color |Conclusion | |control |Control |(Result) | | |Dark Blue |Clear |Dark Blue |Sugar! |
Starch was the next experiment. Like in the name, the Starch test was positive for starch. One...