Lab 2aDISSECTING A CELL:
Purpose - indicator solutions to test for proteins, carbohydrates, and fats. Materials - Eggs, 250 ml breaker, white vinegar, plastic wrap, slotted spoon, sodium chloride, distilled water, 100 ml beaker, 5 ml pipets, green pipet pump, 13x100 mm glass tubes, peg racks for 13x100 mm tubes, glucose, Benedict's solution, hot plate stirrer, test tube holder, soluble starch, Lugol's Iodine Solution, vortex mixer, gelatin, sodium hydroxide, cupric sulfate 5-hydrate, oil, Sudan IV, scalpel handles #4, scalpel blades #22, plastic trays Procedure: PART I
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Part II
Monosaccharide Indicator Standard Test Test for glucose by mixing the 2% glucose solution with 2 mL of Benedict's Solution. Heat for 2 mins in a boiling hot water bath. Record all color changes and the lengths of time for each color to appear. Test for water by mixing 2 mL of deionized water with 2 mL of Lugol's iodine and gently swirling to mix. Heat for 2 mins. Record color changes again. Results: Starch indicator Test Test for starch by mixing 2mL of well-mixed starch indicators with 0.25 mL of Lugol's Iodine. Gently swirl to mix. DO NOT HEAT! Record color change. To test for water, mix 2 mL of deionized water with 0.25 ml of Lugol's Iodine. Gently swirl to mix. DO NOT HEAT! Record color change. Protein Indicator Test Test for proteins. Place 2 mL of gelatin in a test tube. Wearing safety equipment, add 1 ml of Biuret solution. Record color change after 30 seconds. Do the same for water. Lipid indicator Standard Test Test for lipids: Add 60 ul of Sudan IV to the substance being tested. Orange is positive. Part III
Molecular Composition of Egg Components Conduct each indicator test from part II but substitute each egg component to be tested. Do not add any standard solutions! Record the results for each of the egg components. |
Data and results
Part I
Egg observations:
Day 1:
Our egg was put into a beaker full of vinegar.
Day 2:
Shell was dissolved and the egg was smaller.
Day 3:
water moved inside the egg and made it bigger... when the egg was cut in part III, it burst due to the internal pressure.
Part II
Glucose Test: While the test tube was in the hot water, it changed colors. First, it was green and then it turned black.
Starch Test: The starch test turned blackish purple from a clear color.
Protein Test: The test was positive.
Lipid Test: The lipid test was yellow. This makes it positive.
Egg observations:
Day 1:
Our egg was put into a beaker full of vinegar.
Day 2:
Shell was dissolved and the egg was smaller.
Day 3:
water moved inside the egg and made it bigger... when the egg was cut in part III, it burst due to the internal pressure.
Part II
Glucose Test: While the test tube was in the hot water, it changed colors. First, it was green and then it turned black.
Starch Test: The starch test turned blackish purple from a clear color.
Protein Test: The test was positive.
Lipid Test: The lipid test was yellow. This makes it positive.
Reflection: Over all, I think this project went very well. I was partners with Archer and I think we worked very well together. Sometimes we would bicker over who would get to do what steps but otherwise it went well. One thing that we could have changed was the amount of human error. I believe that some of our tests were not as exact as they could have been.