Question 1. Any enzyme converts substances generally known as substrates into substances commonly called products. For the reaction shown above, name the substrates and products below. Then label them on the drawing above.
substrate(s):
product(s):
Table 1: Benedict's Test on Known Solutions
Test Tube Number
Test Solution
Benedict's Test Results:
Color
Benedict's Test
Results:
Precipitate
(-, +, ++, +++, etc.)
1
1% sucrose
2
1% fructose
3
1% glucose
4
DI* water
- deionized water (water which contains no ions)
Question 3. What was the purpose of testing deionized water?
Question 4. A student arrives at the lab on Saturday. S/he wants to verify that the stock invertase solution left over from Friday's lab is still "good". The student mixes some 1% sucrose and some of the stock enzyme solution in a test tube and lets it stand in the test tube rack for one-half hour. Then the student performs a Benedict's test on the test tube contents.
What is the correct interpretation of the Benedict's test if the result is a clear, blue solution? Is the enzyme active or not?
What is the correct interpretation if Benedict's test shows a bright orange precipitate? Is the stock enzyme still "good"?
Question 5. Based on what you already know about living things, in what general range of temperature do you expect enzyme molecules to function best? We will have 4 “groups.”
What is the dependent variable?
What is the independent variable?
State your answer as a hypothesis for this part of the exercise in an If…, and …, then … format.
Sample Solution