1. Which tubes showed that starch or cellulose was still present?
2. Which tubes tested positive for the presence of reducing sugars?
3. What was the effect of freezing tube 1?
4. How does the effect of freezing differ from the effect of boiling?
5. Does amylase use cellulose as a substrate? Hint: Look at the results for tube 4.
6. What effect did the addition of bacteria have on the digestion of cellulose?
7. What was the effect of the different enzyme, peptidase, used in tube 6? Explain your answer, based on what you know about the substrate of peptidase.