Researchers conducted an experiment to evaluate the inhibitory effect of copper sulfate (CuSO4) on the enzymatic activity of catalase, which breaks down hydrogen peroxide (H2O2) into water and oxygen. Four test tubes were prepared under identical temperature and pH conditions:
- Tube 1: 5.0 mL H2O2 solution + 1.0 mL distilled water (No catalase enzyme, no CuSO4)
- Tube 2: 5.0 mL H2O2 solution + 1.0 mL catalase solution (Catalase present, no CuSO4)
- Tube 3: 5.0 mL H2O2 solution + 1.0 mL catalase solution + 0.1 mM CuSO4
- Tube 4: 5.0 mL H2O2 solution + 1.0 mL catalase solution + 1.0 mM CuSO4
Match each experimental setup on the left with its intended baseline or experimental role on the right.
- Tube 1 (H2O2 + Distilled water)Negative control to confirm baseline H2O2 decomposition without enzyme activity
- Tube 2 (H2O2 + Catalase enzyme + Distilled water)Positive control/baseline group to establish maximum enzyme activity without inhibitor
- Tubes 3 and 4 (H2O2 + Catalase enzyme + CuSO4)Experimental treatment groups to evaluate the effect of varying inhibitor concentration
Answer
Tube 1 matches the negative control for non-enzymatic breakdown; Tube 2 matches the positive control baseline for uninhibited enzymatic activity; Tubes 3 and 4 match the experimental treatment groups testing inhibitor concentration.
In experimental design, control groups provide benchmark comparisons. Tube 1 isolates non-enzymatic reaction rates (negative control), Tube 2 isolates uninhibited enzymatic reaction rates (baseline/positive control), and Tubes 3 and 4 assess the specific impact of adding the inhibitor variable.
Step-by-Step Solution
Key Concept
Determining Control Groups and Baseline Conditions