Macromolecule Lab Answers 5e6b6j

Macromolecule Lab Ravi Patel 3.1 Proteins

Table 3.2 Biuret Test Tube

Contents

Final Color

1

Distilled water

Transparent, light blue, navy Dark Purple Purplish blue, darkish blue Light blue, really clear

2 3 4  

Conclusions

Possibly little protein with clear peptide or no protein at all Albumin Proteins are present with purple peptides Pepsin Proteins are present with purple or black colored peptides Starch Possible little protein with clear peptide or no protein at all Our results are correct because water and starch should not contain protein (starch is a polysaccharide but not of an amino acid) and therefore remained blue unlike Albumin and Pepsin which do contain proteins causing them to turn into a different color. Test tube # 1 is the controlled sample; a controlled sample is an experiment under regular conditions. Experiment Procedure include controlled sample in order to indentify the difference between the regular conditions and the experimented conditions.

3.2 Carbohydrates

Table 3.3 Iodine (IKI) Tests for Starch Tube

Contents

1 2

Water Starch Suspension

3 4 5   

Color

Conclusions

Dark amber, maple syrup Does not contain starch Dark amber red, almost Contains starch black Onion Juice Ketchup red, gold tint Contains a slight amount of starch Potato Juice Black brownish Contains starch Glucose solution Amber red Does not contain starch Our results were accurate and did not contain any unexpected results. Since water and Glucose shouldn’t contain starch they appeared to be yellowish-brown. But starch suspension, onion juice, and potato juice should contain starch and therefore changed color. Potato: o . o . Onion: o Under the microscope onion did not contain starch, but after some research, I have discovered that onions actually contain glucose, a component of starch, but when tested with iodine for starch (as we did in class) it will result negative because glucose is a simple sugar.

Table 3.5 Benedict’s Reagent Test Tube 1 2 3 4 5   

Contents

Color (After Heating)

Conclusions

Water Dark blue Contains no sugars Glucose solution Forest green Contained very low amount of sugar Onion Juice Bright orange Contained High amount of sugar Potato Juice Turquoise Contained very low amount of sugar Starch Electric blue Contained no sugars Suspension In table 3.5, test tube 1 served as the controlled sample When table 3.3 and 3.5 are compared these are the ending results: o Water is the controlled sample and does not contain sugars o Onion Juice contains sugars as well as potato juice Glucose is stored as starch in potatoes but not so much in onions. This helps explain the results in table 3.5 because since potato juice stores glucose as starch (proven in table 3.3) it showed that it contained less sugar not in the form of starch, but when onion juice was tested, it

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Macromolecule Lab Ravi Patel resulted in containing small amounts of starch (proven in table 3.3) but high amounts of sugar not in the form of starch.

Starch Composition

Table 3.6 Starch Composition Tube

Contents

1 2

Water & Spit Starch & Spit



Color Change

Conclusions

Clear blue, floating particles (bubbles) Blue at bottom and gradually become white as you go up (Spectrum goes from blue to white) and substance is very thick Starch is composed of sugars (preferably glucose monomers)

No sugar or maltose Some maltose because it became clear and thick

Test for Lipids

Table 3.7 Test for Lipids Sample

Observations

Conclusions

Water Spot

Water Spread out instantly consuming almost 3 times the original radius of the droplet out of the square paper. After 5 min it had almost spread out across 90% of the paper and had successfully penetrated the paper but also evaporated a little. Started to spread out at a very slow and gradual rate, and left a shine. After 5 min it still remained on top.

Water is not a fat because it started evaporating a little and didn’t leave an oily spot

Oil Spot

Oil is a fat because it didn’t evaporate and left an oily spot

Emulsification of lipids  

Test tube 1: Vegetable oil is not soluble in water Test tube 2: The oil seems to have been distributed in the water, though it has not been dissolved.

Table 3.8 Emulsification Tube

Contents

Observations

1

Oil Water

Large bubbles of oil in the water

2 



Conclusions

Oil is non-polar and therefore did not dissolve in the water Oil Water Seems to be like a huge cell. Small The emulsifier helped distribute Emulsifier particles enclosed in a large circle the oil among the water Test tube 1 looked like 2 different layers to the unaided eye. But when it was closely examined under a microscope, it showed a few bubble in the water. Similarly to the unaided eye view, the oil is still separated from the water. Test tube 2 looked as if the oil had dissolved in the water when viewed without the microscope. But when it was magnified, it showed that the oil had not dissolved, instead it had only been dispersed into the water.

3.4 Testing the Chemical Composition of Everyday Materials and an Unkown

Table 3.9 Everyday Materials and Unknowns Tube

Sugar

Starch

Protein

Lipid

1

Baby/Solid Blue

Black

Expanded fast

2 3 4

Cloudy Turquoise Forest Green Crystal dark/sky blue

Mud/dark green Dark amber Muggy orange

Light Blue Clouds Golden dirt rain Foggy Purple Foggy Purple

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Yellow in Center Expanded slowly White Substance in middle

Macromolecule Lab Ravi Patel 5

Clear blue

 

Cloudy amber

Clear Purple

Expanded very fast then slowed down Yes, there are many materials that resulted positive in multiple organic compounds. Such as Test tube number 3, which contains sugars and expanded slowly meaning it’s a lipid. One type of food would be a potato (containing starch and sugars) or milk (containing sugars and proteins)

Laboratory Review 3 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14.

Peptide Bond Enzymes and/or Catalysts Amino Group and Carbonyl Group Starch Glucose or Maltose Starch is stored as granules within cellular structures called plastids, including chloroplasts. By synthesizing starch, the plant can stock pile surplus sugar. Starch is composed entirely of glucose monomers Major function of fat is energy Storage When fat is hydrolyzed, the fatty acid molecules are released An emulsifier can help disperse a fat in water Fats are non-polar Proteins A very long time because eggs do not contain much starch Benedict’s Reagent

Thought Questions 15.)It is necessary to shake a bottle of salad dressing before adding it to the salad because most of the fats are on top and the other substances are on the bottom, and in order to get a good ration of fats to the other substances, a good shake is required. 16.) These results are considered negative because Blue is the original color of both of those reagents, which means that neither of them reacted meaning that the substance has neither starch or sugar. Since they were not present the result is negative. If they had been present the result would have been positive.

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