You will use this document to:
• Record your data from the lab experiments.
• Turn in your preliminary findings for Week 2.
Indicator tests
Identify which chemical indicates which nutrient is present. The first indicator has been noted. (10 pts)
Indicator test Tests for … Negative result (color) Positive result (color)
Benedict’s solution
Prediction Table – Record a hypothesis for each food by listing the food to be tested and indicating which of the organic molecules you believe to have the highest concentration in each food. Use an X to mark the appropriate box. (12 pts)
Type of Food Glucose Starch Protein Lipids Vitamin C
1.
2.
3.
4.
5.
6.
Experiment 1 – Test for Glucose (12 pts)
Type of Food Starting Color Resulting Color Test Positive/Negative
1.
2.
3.
4.
5.
6.
Experiment 2 – Test for Starch (12 pts)
Type of Food Starting Color Resulting Color Test Positive/Negative
1.
2.
3.
4.
5.
6.
Experiment 3 – Test for Protein (12 pts)
Type of Food Starting Color Resulting Color Test Positive/Negative
1.
2.
3.
4.
5.
6.
Experiment 4 – Test for Lipids (12 pts)
Type of Food Lipid Not a Lipid
1.
2.
3.
4.
5.
6.
Experiment 5 – Test for Vitamin C (12 pts)
Type of Food # of drops
1.
2.
3.
4.
If you do not have or cannot obtain the liquid items listed in #3 of this experiment, choose 3 other liquid drinks to test.
Additional questions: You may need your book in addition to the lab results to answer these questions. (1 pt each unless otherwise noted)
1. Do you believe that Benedict’s solution would give a positive reaction for all carbohydrates? Why or why not?
2. Put a drop of Lugol’s iodine on the corner of a piece of paper. Does paper contain starch?
3. What are the 3 components (chemical elements) of a molecule of carbohydrate?
4. What are the component molecules that form together to make a triglyceride?
5. What are the building blocks of proteins?
6. How would you determine whether coconut milk contains glucose?
7. What could you say about a substance if it did not turn blue-black with iodine?
8. What does “hydrogenation” mean?
9. List the 3 types of carbohydrates, and give an example of each. (6 pts)
a.
example:
b
example:
c.
example:
10. Why might you be asked to test water for each experiment?
11. Is it possible for a food to contain more than one organic molecule? Explain.
12. Do you think it would make a difference in the lipid stain test if a fatty acid was saturated or not saturated? Explain.
13. How many total amino acids exist? How many of these are essential and how many are nonessential?