Dissecting a cell and examining its components
Purpose:
Positive indicator tests for protein, carbohydrates, and fat.
Test egg parts for protein, carbohydrates, and fat.
Materials:
Procedure:
PART I
Monosaccharide Indicator Standard Test
1. Mix Biuret and gelatin in a test tube. Record color changes.
2. Mix deionized water and Biuret in a test tube. Record color changes.
Lipid Indicator Standard Test
1. Mix Sudan IV and oil. Record color change.
2. Mix deionized water and Sudan IV. Record color changes.
Part III
1. Use indicator tests to test egg parts for sugar, starch, protein, and fat.
2. Record the results of each component.
3. Label each test result depending on how strong or weak each color change was.
Data/Results:
Part I
CaCO3 + CH3COOH -> H2CO3 + H2O + CO2
Day 1 : We put the egg in vinegar in order to dissolve the shell.
Day 2: The shell was dissolved. We then put the egg in NaCl.
Day 3: We put the egg in deionized water. The water seemed to go into the egg. The egg seemed much bigger than it had been before. We know the water did go into the egg because the egg burst open when we made a slit in it.
Positive indicator tests for protein, carbohydrates, and fat.
Test egg parts for protein, carbohydrates, and fat.
Materials:
- Eggs
- Beaker, 250 mL
- White vinegar
- Plastic wrap
- Slotted spoon
- Sodium chloride
- Distilled water
- Beaker, 100 mL
- Pipets, 5 mL
- pipet pump, green
- Tubes, glass, 13x100 mm
- Peg racks for 13x100 mm tubes
- Glucose (dextrose)
- Benedict's Solution
- Hot plate stirrer
- Test tube holder
- Starch, soluble
- Lugol's Iodine Solution
- Vortex mixer
- Gelatin
- Sodium hydroxide
- Cupric sulfate 5-hydrate
- Oil
- Sudan IV Solution
- Scalpel handles, #4
- Scalpel blades, #22, for #4 handles
- Trays, plastic
Procedure:
PART I
- Put an uncooked egg in a beaker filled with white vinegar. Cover the beaker with plastic wrap. Make sure to label it. Leave the egg for 24 to 48 hours and wait for it to dissolve.
- After this period of time the shell should have dissolved. Use the slotted to spoon to carefully pick up the egg and rinse the vinegar off. A chemical reaction has happened.
- Feel the outer membranes. This membrane is a good model of a cell membrane. They are thin and flexible, and they are permeable to some substances. Put the egg in 5% NaCl solutions for a full day.
- Rinse egg and put it in distilled water for 24 hours.
- Make a slit in the membrane, and allow the egg whites to drip out. Don't pierce the yolk.
- Put the egg yolk in a different beaker than the egg membranes.
Monosaccharide Indicator Standard Test
- Glucose test: Mix glucose solution with Benedict's Solution. Heat in boiling water bath. Observe and write down color changes.
- Water test: Mix deionized water and Benedict's solution. Heat in boiling hot water bath. Observe and write down color changes.
- Starch test: Mix well-mixed starch suspension with Lugol's iodine. Write color changes.
- Water test: Mix deionized water with Lugol's iodine. Write color changes.
1. Mix Biuret and gelatin in a test tube. Record color changes.
2. Mix deionized water and Biuret in a test tube. Record color changes.
Lipid Indicator Standard Test
1. Mix Sudan IV and oil. Record color change.
2. Mix deionized water and Sudan IV. Record color changes.
Part III
1. Use indicator tests to test egg parts for sugar, starch, protein, and fat.
2. Record the results of each component.
3. Label each test result depending on how strong or weak each color change was.
Data/Results:
Part I
CaCO3 + CH3COOH -> H2CO3 + H2O + CO2
Day 1 : We put the egg in vinegar in order to dissolve the shell.
Day 2: The shell was dissolved. We then put the egg in NaCl.
Day 3: We put the egg in deionized water. The water seemed to go into the egg. The egg seemed much bigger than it had been before. We know the water did go into the egg because the egg burst open when we made a slit in it.
Part II
Part III
Data analysis
Testing for proteins, carbohydrates, and fats was fairly simple. In order to test for these, you must first compare solutions using a control. Solutions with the control will result in a positive test with some sort of color change. For example when we mixed gelatin and Biuret, the solution turned a light purple color. When the control is taken away, the test will have a negative result. After finding what the results of the positive and negative tests looked like, it was time to test the different parts of the egg. The egg whites tested positive for every component. Our egg whites tested very strongly for glucose and protein. The egg yolk tested positively for glucose, proteins, and lipids. The egg membrane had weak positive tests to glucose and protein.
Some of our results did not match up completely with other groups. There was some errors that led to these different results. First of all when we were testing solutions that needed to be heated, we did not check the temperature before placing the test tubes in the hot water baths. We also could have been even more precise with our measuring. I believe that after a little bit more practice with the pipets and pipet fillers we will be able to measure a much more accurate amount. In order to make this experiment more accurate perhaps we could do a less extensive lab that teaches us how to use the equipment properly and to its full potential.
We use indicator tests in other ways throughout our lives. Indicator tests are used to detect drug use. We also use indicator tests for measuring sugar levels. This is very important for people with diabetes.
Some of our results did not match up completely with other groups. There was some errors that led to these different results. First of all when we were testing solutions that needed to be heated, we did not check the temperature before placing the test tubes in the hot water baths. We also could have been even more precise with our measuring. I believe that after a little bit more practice with the pipets and pipet fillers we will be able to measure a much more accurate amount. In order to make this experiment more accurate perhaps we could do a less extensive lab that teaches us how to use the equipment properly and to its full potential.
We use indicator tests in other ways throughout our lives. Indicator tests are used to detect drug use. We also use indicator tests for measuring sugar levels. This is very important for people with diabetes.
Reflection
I learned a lot while doing this lab. I learned how to use indicator tests, and I learned how they work. My favorite part of the lab was going into the lab everyday and seeing how the egg had changed over night. I especially liked seeing the egg one the shell had dissolved. It was very interesting seeing how the controls worked for the positive tests. I enjoyed watching the solutions change colors. I liked learning how to use new lab equipment such as the pipet fillers and the vortexes.
My partner throughout this lab was Ingrid Borgesen. I believe that we worked extremely well together. We didn't have any issues with dividing the work evenly. We were both very cooperative and shared our own ideas, as well as listen to each other's ideas. We kept up positive attitudes during the entire lab. Overall we worked well, got everything done, and even had fun!
If we were to do this experiment again I wouldn't change that much. First of all I would do a better job with labeling pipets. Sometimes we would mix up the pipets, so we would have to open new ones so that we weren't cross contaminating. Secondly, I would have worked in bigger groups, so that we could be more efficient with our time. Lastly, I would personally like to take more organized and in depth notes on what was happening.
My partner throughout this lab was Ingrid Borgesen. I believe that we worked extremely well together. We didn't have any issues with dividing the work evenly. We were both very cooperative and shared our own ideas, as well as listen to each other's ideas. We kept up positive attitudes during the entire lab. Overall we worked well, got everything done, and even had fun!
If we were to do this experiment again I wouldn't change that much. First of all I would do a better job with labeling pipets. Sometimes we would mix up the pipets, so we would have to open new ones so that we weren't cross contaminating. Secondly, I would have worked in bigger groups, so that we could be more efficient with our time. Lastly, I would personally like to take more organized and in depth notes on what was happening.