1. Practical planning
Independent/dependent/control variables
Fair test design and validity
2. Controls in experiments
Control solution selection
Why controls are essential
3. Risk & ethics
Hazard-risk-precaution structure
Biological sample handling
4. Microscopy measurement
Eyepiece graticule calibration
Cell-size conversion and ratios
5. Biological drawing
Biological drawing conventions
Scale line and magnification usage
6. Qualitative tests
Benedict/Fehling glucose testing
Biuret protein testing
7. Quantitative assays
DCPIP assay design
Calibration curve application
8. Dilution & preparation
Serial dilution calculations
From stock to working solution
9. Enzyme practicals
Initial-rate method
Temperature/pH interpretation
Edexcel IAL Biology
Unit 3 (WBI13/01)
10. Data processing
Mean and standard deviation
Error bars and overlap judgement
11. Graph skills
Table construction from graph
Plotting and best-fit lines
12. Statistical judgement
Justifying conclusions using SD
Avoiding over-claims
13. Accuracy & reliability
Accuracy vs precision vs reliability
Method improvements
14. Core practical biology
Plant tissue micrograph interpretation
Mitosis/meiosis observation logic
15. Reproduction practicals
Pollen germination experiments
Reproductive-structure analysis
16. Maths in U3
Percentage change and ratios
Units and significant figures
17. Extended responses
High-quality method descriptions
Evaluation structure and QWC
18. Command-word control
Describe vs Explain vs Justify
Using mark-scheme language