Overall Score: 14/24
IB Grade: 5
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General feedback
14/24
0
12
24
5.1·suggestion
Page 4
The safety section refers to general lab etiquette but lacks specific precautions for handling pressurized CO₂ probes; add details on securing the probe and monitoring pressure.
5.2·suggestion
Page 4
Ethical considerations mention capping containers to avoid spills but omit protocols for disposing of yeast cultures; include a biohazard disposal step.
Criteria A: Research Design
4/6
0
3
6
Criteria Strands
Excellent
Research question context
Excellent
Methodological considerations
Good
Methodology description
Criteria Feedback
- Research question is precisely defined, with organism, variables, units and specific biofuel context.
- Clear, discipline-specific rationale in background, including glycolysis and substrate selection.
- Well-justified control of key variables (temperature, concentrations, timing) and explicit hypotheses.
- Apparatus details (e.g. water-bath capacity, CO₂ probe settings) are insufficient for full reproducibility.
- Protocol steps lack precise mixing/stirring methods and seal-integrity checks.
- Justification for choice of CO₂ in ppm and 600 s timeframe is not fully explained.
Criteria B: Data Analysis
3/6
0
3
6
Criteria Strands
Good
Communication of data recording and processing
Moderate
Consideration of uncertainties
Good
Data processing quality
Criteria Feedback
- Data processing includes correct calculation of CO₂ change, means and standard deviations for key trials.
- Tables and graphs communicate results clearly, with appropriate units and rounding conventions.
- Error bars are plotted to indicate uncertainty visually.
- Uncertainty is not properly propagated (root-sum-square not used, and not carried through means/rates).
- Some raw data entries are missing or uneven (e.g. lactose trials omitted, inconsistent trial counts).
- Lack of formal statistical analysis (e.g. significance testing) limits precision of conclusions.
Criteria C: Conclusion
4/6
0
3
6
Criteria Strands
Excellent
Conclusion relevance and consistency
Good
Scientific context comparison
Criteria Feedback
- Conclusion directly addresses and rejects the null hypothesis, aligning closely with processed data and trends.
- Comparison of substrate ranking with accepted literature highlights meaningful discrepancies.
- Logical linkage between data and judgment shows clear relevance and consistency.
- No inferential statistical test or error-margin citation to fully justify significance of conclusions.
- Quantitative deviations from literature order are not expressed numerically (e.g. percentage differences).
- Contextual explanation of discrepancies could be deepened with additional literature support.
Criteria D: Evaluation
3/6
0
3
6
Criteria Strands
Good
Methodological weaknesses
Excellent
Improvements
Criteria Feedback
- Specific methodological limitations (uneven mixing, oxygen intrusion, solubility issues) are identified and linked qualitatively to data effects.
- Targeted, feasible improvements (standardised mixing, pre-heating, oil layer) are proposed with clear mitigation rationale.
- Use of a limitations–improvements table effectively organizes evaluation.
- Depth of impact analysis varies; some limitations (e.g. equipment precision) are discussed generically rather than in context.
- Relative impact of each weakness on final results is not consistently explored.
- Opportunities to quantify how improvements would improve uncertainty or reproducibility are missed.