Overall Score: 14/24
IB Grade: 5
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Criteria A: Research Design
5/6
0
3
6
Criteria Strands
Excellent
Research question context
Excellent
Methodological considerations
Good
Methodology description
Criteria Feedback
- Research question precisely specifies independent and dependent variables within a clear biochemical context.
- Control variables are comprehensively listed with clear methods and rationales.
- Methodological considerations are well justified by citing prior research on optimal starch concentration.
- Typographical errors in “Repeat steps 2–85 times” create ambiguity in repeat count.
- Iodine–colorimeter procedure lacks explicit timing and measurement-interval details.
- Bundled visual and quantitative measures of the dependent variable are not clearly delineated.
Criteria B: Data Analysis
2/6
0
3
6
Criteria Strands
Good
Communication of data recording and processing
Poor
Consideration of uncertainties
Moderate
Data processing quality
Criteria Feedback
- Raw data tables include units, uncertainties, and descriptive titles.
- Worked example for the 6% concentration calculation clearly demonstrates processing steps.
- Statistical analysis (unpaired t-test) with p-value and confidence interval is appropriately presented.
- Uncertainties listed are not propagated through calculations, and error bars do not derive from uncertainty analysis.
- Graph axes are mislabeled (‘light absorbance’ vs. ‘transmission’) and omit units and error bars.
- Negative reaction rate at 4% is noted but not analyzed or explained.
Criteria C: Conclusion
4/6
0
3
6
Criteria Strands
Excellent
Conclusion relevance and consistency
Good
Scientific context comparison
Criteria Feedback
- Conclusion clearly restates the aim and identifies 6% starch as yielding the highest activity, supported by mean rates and statistical significance.
- Comparison to Gebreyohannes (2015) situates results within accepted scientific context and justifies methodological discrepancies.
- Brief treatment of the anomalous negative rate at 4%; kinetic or measurement-error analysis is needed to fully justify consistency.
- Discussion of differences in pH and temperature effects is sound but could be more analytically detailed.
Criteria D: Evaluation
3/6
0
3
6
Criteria Strands
Moderate
Methodological weaknesses
Moderate
Improvements
Criteria Feedback
- Specific methodological weaknesses (temperature drift, volumetric inaccuracies, qualitative iodine endpoint) are identified.
- Improvements (use volumetric pipette, relocate colorimeter, extend duration) are realistic and directly address identified issues.
- Acknowledgement of limitations in the qualitative iodine test demonstrates critical evaluation of reliability concerns.
- No quantitative estimation of how temperature drift or volumetric error impacts results.
- Suggested improvements are described but lack detailed explanation of how they would enhance validity.
- Innovative proposals (e.g., testing mango amylase) need clearer justification in relation to the research question.