What is your hypothesis?
I believe that the substrate of lactose will work best with pH levels of 7 because that is the pH level best reactive with water (used to bond the two sugars, galactose and glucose) and found within our bodies.
Record your data:
Table 1: Record your data on the number of product molecules formed per minute obtained from the virtual lab.
# Product Molecules/minute at:
Amount

pH 3

pH 5

pH 7

pH 9

pH 11

of
Substrate
(Lactose)
0.5 g

19

39

72

45

24

1.0 g

39

81

145

91

49

2.0 g

82

168

300

189

103

4.0 g

96

198

350

223

121

8.0 g

96

198

350

223

121

Graph your data and put the graph here.

Now answer the following questions about your results:
1. What substrate amount was required to achieve the maximum reaction rate?
4 grams of lactose was the amount that achieved the maximum rate.

2. At what pH level did the maximum reaction rate occur? pH level 7 was the maximum reaction rate found in all amounts of substrate used.
3. Why was there no increase in the reaction rate with 8.0 g. of substrate as compared to 4.0 g. of substrate? What would you need to add to see an increase in the reaction rate with 8.0 g. of substrate?
There was no increase in reaction rate with 8 grams compared to 4 grams because there was not enough lactase solution.
4. In the graph you created in the lab simulation with your data:
■ What is represented by the green line? pH level 7
■ What is the optimal pH for lactase enzyme activity? pH level 7
5. Consider only the experiment you conducted with 0.5 g. of lactose.
■ What is the independent variable?
0.5 g of lactose
■ What is the dependent variable? pH levels