Question 1
According to Table 1, how much O₂ was produced at 30°C after 120 seconds?
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Data Representation · biology0/0 correct · 5 questions
Effect of Temperature on Catalase Activity
Catalase is an enzyme found in nearly all living organisms. It catalyzes the decomposition of hydrogen peroxide (H₂O₂) into water (H₂O) and oxygen gas (O₂). A group of students investigated how temperature affects the rate of catalase activity.
The students prepared 6 identical test tubes, each containing 5 mL of a 3% hydrogen peroxide solution. They added 1 mL of catalase solution (extracted from potato tissue) to each tube. Each tube was maintained at a different temperature using water baths. The students measured the volume of oxygen gas (in mL) produced after 30 seconds, 60 seconds, 120 seconds, and 180 seconds. The results are shown in Table 1 and described in Figure 1.
All other conditions — including the concentration of H₂O₂, the volume and concentration of catalase solution, and the pH of the solution (pH 7.0) — were held constant across all trials.
Table 1. Volume of O₂ produced (mL) at various temperatures over time
| Temperature (°C) | 30 s (mL) | 60 s (mL) | 120 s (mL) | 180 s (mL) |
|---|---|---|---|---|
| 10 | 0.5 | 1.2 | 2.1 | 2.8 |
| 20 | 1.3 | 2.8 | 5.0 | 6.5 |
| 30 | 2.4 | 5.1 | 9.2 | 11.8 |
| 37 | 3.1 | 6.8 | 12.5 | 16.0 |
| 50 | 1.8 | 3.5 | 5.8 | 6.9 |
| 60 | 0.3 | 0.5 | 0.6 | 0.6 |
Figure 1. Total O₂ produced at 180 seconds vs. temperature
A line graph with temperature (°C) on the x-axis (from 10 to 60) and total O₂ produced at 180 s (mL) on the y-axis (from 0 to 18). The curve rises steeply from 10°C (2.8 mL) to a peak at 37°C (16.0 mL), then drops sharply to 60°C (0.6 mL), forming a bell-shaped curve. The peak of the curve is at approximately 37°C.
x-axis: Temperature (°C) · y-axis: Total O₂ produced at 180 s (mL)
Question 2
Based on Figure 1, which of the following best describes the relationship between temperature and catalase activity over the range tested?
Question 3
Based on the data in Table 1, if the experiment were repeated at 25°C, the volume of O₂ produced after 180 seconds would most likely be closest to:
Question 4
At which temperature did the difference in O₂ volume between the 60-second and 180-second measurements reach its greatest value?
Question 5
At 60°C, O₂ production nearly stopped after 60 seconds (only 0.1 mL additional O₂ was produced between 60 s and 180 s). Which of the following best explains this observation?