For a words-in-context question, distinguish a broad verb describing a process from a more precise verb describing the process's result. Track how the later evidence changes the original explanation, and use qualifying language to decide whether that explanation was strengthened, reduced in importance, or eliminated.
Hints
- Hint 1
Track the proposed mechanism
Identify which mechanism was initially treated as the primary explanation and which different mechanism gained support from the later evidence.
- Hint 2
Distinguish process from outcome
Determine not merely whether the researchers reconsidered the proposed mechanism but how its relative explanatory importance changed. Also note that the text does not rule the mechanism out completely.
Step-by-step
- Step 1
Identify the proposed mechanism
The researchers initially attributed the activity loss primarily to the tag's histidines chemically disrupting the enzyme's metal-containing active site.
- Step 2
Evaluate the later evidence
The unattached tag had no effect, relocating the attached tag restored much of the activity, and simulations indicated that the tag could obstruct the substrate channel. These findings support a position-dependent physical mechanism, while the possible weak chemical interactions leave the original mechanism viable as a lesser contributor.
- Step 3
Choose the most precise verb
The researchers did more than merely reconsider the chemical mechanism, but they did not eliminate it. They deemphasized it by assigning it less explanatory importance than it initially had.