2020 Modified Biochemistry Lab-- use notes/text to assist :) cloned 9/27/2020 cloned 10/15/2020

Last updated about 5 years ago
24 questions
Modified Macromolecule Lab... ** NOTE THAT THERE WILL BE NO FEEDBACK ON THIS GOFORMATIVE AND IT IS DUE ON MONDAY, 11/2 BY 10 A.M.

Each of the procedures below can be used to test for organic compounds in a sample:

Polysaccharides (Iodine Test)

1. Place your sample into a petri dish or test tube.
2. Put 3 to 5 drops of iodine onto your sample.
3. Note the results- black indicates a positive result.

Monosaccharides & Reducing Disaccharides (Benedicts Test)

1. Place your sample in a test tube.
2. Put 3 to 5 drops of Benedict’s solution onto your sample
3. Place the test tube into a hot water bath.
4. Allow the sample to sit in the hot water bath for 2 to 3 minutes.
5. Carefully remove your test tube with a test tube clamp and note the results- green, yellow and orange indicate a positive result.

Proteins (Biuret Test)
1. Place a your sample in a petri dish or test tube.
2. Put 3 to 5 drops of Biuret solution onto your sample.
3. Note the results- violet indicates a positive result.

Lipids (Litmus or Sudan IV Test)
1. Dip your litmus test strip into your sample or add 3-5 drops of Sudan IV reagant.
2. Note the results (light pink= no lipids, red= lipids present)

Again, how to read positive results:
+ polysaccharides= black
+ protein= dark violet/purple
+ lipids= oil ring (for paper blotter), red color (for Sudan IV litmus test strip)
+ monosaccharides/disaccharides= yellow/orange/green
1

Let's practice proper hypothesis writing.... choose the BEST answer for this lab. Gelatin, amino acids, glucose, starch and vegetable oil will be tested.

Gelatin:

1

Let's practice proper hypothesis writing.... choose the BEST answer for this lab. Gelatin, amino acids, glucose, starch and vegetable oil will be tested.

Amino Acids:

1

Let's practice proper hypothesis writing.... choose the BEST answer for this lab. Gelatin, amino acids, glucose, starch and vegetable oil will be tested.

Glucose:

1

Let's practice proper hypothesis writing.... choose the BEST answer for this lab. Gelatin, amino acids, glucose, starch and vegetable oil will be tested.

Starch:

1

Let's practice proper hypothesis writing.... choose the BEST answer for this lab. Gelatin, amino acids, glucose, starch and vegetable oil will be tested.

Vegetable oil:

Now, let's review the results...
5

What were the color change results???

Draggable itemCorresponding Item
negative result: no color change
starch solution
positive result: black
vegetable oil solution
positive result: red
gelatin solution
positive result: purple
glucose solution
positive result: yellow
amino acid solution
12

What were the test results??? ** since vegetable oil was not included with the other biomolecules, it will be excluded in this section of results. ***Be sure to indicate all positive and negative results below.

  • Positive for Benedicts (+)
  • Positive for Biuret (+)
  • Negative for Iodine (-)
  • Positive for Iodine (+)
  • Negative for Benedicts (-)
  • Negative for Biuret (-)
  • gelatin solution
  • glucose solution
  • starch solution
  • amino acid solution
Now, some more foundational practice 🤓
2

Which test(s) would indicate for the presence of (C6 H12 O6) ?

2

Which test(s) would indicate for the presence of (C12 H22 O11)?

2

Which test(s) would indicate for the presence of (C24 H42 O21)?

1

Which test(s) would indicate for the presence of waxes?
Which test(s) would indicate for the presence of cellulose?
Which test(s) would indicate for the presence of actin/myosin?

Indicate in proper order.

3

Of the organic compounds (starch, glucose, amino acids, vegetable oil, and gelatin) tested for in the video experiment, which were monomers?

2

Of the organic compounds (starch, glucose, amino acids, vegetable oil, and gelatin) tested for in the video experiment, which were polymers?

1

Explain what denaturation is. **Be sure to use your own words- this program flags copied/pasted answers.

1

At what levels can a protein denature?

1

What factors that can affect protein function?

1

What are the FUNCTIONS of fats? Hint... you may want to consult your notes/text.

1

What are the main FUNCTIONS of proteins. Hint... you may want to consult your text/notes.

1

What are the FUNCTIONS of nucleic acids? Hint... you may want to consult your notes/ text.

1

What protein molecule aids in the folding process of proteins? Hint... you may want to consult your notes/textbook.

1

How can misfolding can affect cells... what 3 diseases that may occur as a consequence). Hint.... consult your text!

1

Describe the difference between a glycosidic link and a peptide bond.

1

What is the name of the bond that holds two nucleotides together at their nitrogenous bases?

1

What are the differences between saturated and unsaturated fats in terms of structure and function.

If you need a refresher, here is the Bozeman video on biomolecules :) Ready to practice specifically with proteins?