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Problem 13 - Entrance Test

A biochemist studies the activity of Enzyme X at various pH levels. The optimal pH for most enzymes is typically within a narrow range. The table below shows the relative activity of Enzyme X at different pH values. | pH Value | Relative Enzyme Activity (%) | |---|---| | 4.0 | 20 | | 5.0 | 45 | | 6.0 | 80 | | 7.0 | 95 | | 8.0 | 90 | | 9.0 | 10 | | 10.0 | 50 | Which data point most likely represents an experimental error or anomaly?

Correct: D

Enzyme activity typically increases to an optimum pH and then decreases. Looking at the trend: activity increases from 4.0 to 7.0 (20% -> 95%), then starts to decrease at 8.0 (90%). At 9.0, it drops further to 10%. However, the activity at pH 10.0 suddenly jumps back up to 50%, which is highly inconsistent with the observed pattern of decreasing activity after the optimum. This sharp increase after a significant drop at pH 9.0 strongly suggests an anomaly or experimental error, as it deviates significantly from the expected trend.