Chemical and Physical Processes of Digestion
LAB DATE/TIMEaugust 4th
The following questions refer to Activity 1: Assessing Starch Digestion by Salivary Amylase.
1.At what pH did you see the highest activity of salivary amylase? Why? 7.0 because that is when the salivary is most effective and it breaks down carbohydrates.
2.How do you know that the amylase did not have any contaminating maltose?
We used a negative control to see if there is any amylase in the maltose.
3.What effect did boiling have an enzyme activity? Why?
Boiling denatured the enzyme because it destroys the structure of the protein.
4.Describe the substrate and the subunit product of amylase. The substrate is starch the subunit is reducing sugar.
The following questions refer to Activity 2: Assessing Cellulose Digestion.
5.Does amylase use cellulose as a substrate? Explain.
No because amylase only works on starch and wont digest cellulose.
6.Did freezing have an effect on the activity of amylase? Explain. Freezing does not change the structure of the enzyme so it doesn’t have effect on the activity.
7.Do you think that the bacterial suspension contained the enzyme cellulose (an enzyme that digests cellulose)? Why or why not?
Yes I think the bacteria contained cellulase because it specifically digests cellulose.
Protein Digestion by Pepsin
The following questions refer to Activity 3: Assessing Protein Digestion by Pepsin.
8.What is the substrate of peptidase? Explain, based upon your results. The substrate is a synthetic protein called APNA.
9.At which pH did you see the highest activity of pepsin? How does this correlate to the location of pepsin in the body?