Question

4 The graph below shows how the activity of an enzyme changes

over a range of pH values.
Enzyme Activity
Percent of Maximum Activity
100
90
80
70
60
50
40
30
20
10
0
5.0 5.8 6.6 7.4 8.2 9.0
pH
Which of the following conclusions is supported by the data?
A. The optimum pH of the enzyme is 6.6.
B. The optimum pH of the enzyme is 5.8.
C. The enzyme's activity is greater around pH 8.0 than around
pH 5.0
D
The enzyme's activity continually increases as pH increases
from 5.0 to 9.0

Answer 1

A

Step-by-step explanation:

A. The optimum pH of the enzyme is 6.6. - this is true. The optimum pH of the enzyme is where its activity is the highest. On the graph, this is pH 6.6 (activity at 100)

B. The optimum pH of the enzyme is 5.8. - this is false, the activity of the enzyme peaks at 6.6 (100), at 5.8 the activity is 80

C. The enzyme's activity is greater around pH 8.0 than around pH 5.0 - This is false, the activity at pH 5 is 50, whereas at around 8 it is 20.

D . The enzyme's activity continually increases as pH increases from 5.0 to 9.0 - this is false. The activity drops between pH 6.6 and pH 9.