IB Biology — Diagnostic Guide

Coverage Map

Grading Rubric

PASS Criteria

• Correctly solve at least 2 out of 3 Unit Tests with clear biological reasoning
• Correctly solve at least 2 out of 3 Integration Tests showing cross-topic understanding
• Use correct biological terminology and units throughout
• Demonstrate understanding of underlying mechanisms (not just memorised facts)

PARTIAL Criteria

• Correctly solve 1—2 Unit Tests and 1 Integration Test
• Shows conceptual understanding but with gaps in detail or terminology
• Partially correct explanations with some biological inaccuracies
• Correct calculations but incorrect or incomplete biological interpretation

FAIL Indicators

• Unable to solve any Unit Test completely
• Fundamental misconceptions (e.g., confusing transcription and translation, misunderstanding dominance)
• Cannot connect concepts across topics in Integration Tests
• Systematic errors in genetic crosses or Hardy-Weinberg calculations

Prerequisite Chains

Cell Biology
  └── Molecular Biology
        ├── Genetics
        │     ├── Ecology (population genetics)
        │     └── Human Physiology (immune system, inheritance)
        └── Plant Biology (gene expression in plants)

Ecology (independent foundation)
  └── Plant Biology (productivity, nutrient cycles)

Human Physiology (largely independent)
  └── Connections to Cell Biology (membrane transport, cell signalling)

Recommended order of diagnostic completion:

1. diag-cell-biology — foundational cell concepts
2. diag-molecular-biology — builds on cell biology
3. diag-genetics — requires molecular biology understanding
4. diag-ecology — largely independent, but benefits from genetics
5. diag-plant-biology — requires molecular biology and ecology
6. diag-human-physiology — largely independent, recommended last

Timing Recommendations

Total recommended time: approximately 3.75 hours (spread across multiple sessions).

Full battery timing: Complete all 6 diagnostics over 2—3 sessions of 70—90 minutes each.

How to Use These Diagnostics

1. Complete each diagnostic without referring to notes or textbooks.
2. Check solutions immediately after each question to identify specific gaps.
3. If you score FAIL, review the corresponding source file thoroughly before retrying.
4. If you score PARTIAL, focus revision on the specific concepts from missed questions.
5. Integration Tests are the strongest predictor of exam performance — they test your ability to apply knowledge across topics, which is what IB exams require.
6. Pay particular attention to the quantitative aspects (calculations, statistical tests) as these are frequently tested and easy marks when done correctly.

Summary

The key principles covered in this topic are linked in the sub-pages above. Focus on understanding the definitions, applying the formulas or frameworks, and evaluating strengths and limitations of each approach.

Worked Examples

Worked examples demonstrating the application of key concepts are covered in the detailed sub-pages linked above.

Common Pitfalls

• Confusing terminology or concepts that appear similar but have distinct meanings.
• Overlooking key assumptions or boundary conditions that limit applicability.

Overview

This diagnostic assessment provides comprehensive coverage of Biology content for the Ib qualification, with detailed explanations, worked examples, and practice questions aligned to the specification.

Content Structure

This page includes:

• Key Definitions: Precise explanations of essential concepts
• Core Concepts: Detailed treatment of fundamental principles
• Worked Examples: Step-by-step solutions demonstrating application
• Practice Questions: Examination-style questions with mark schemes
• Common Pitfalls: Frequent errors and how to avoid them
• Exam Tips: Strategies for maximising marks

How to Use This Content

1. Read through the introductory material to establish context
2. Study the definitions and core concepts carefully
3. Work through the worked examples, following each step
4. Attempt the practice questions independently
5. Review your answers against the provided solutions
6. Note any areas requiring further revision

Key Concepts

• Foundational definitions and terminology
• Application of principles to examination contexts
• Connections to related topics within the specification
• Assessment objective alignment

Revision Strategies

• Active Recall: Test yourself on the material rather than passively re-reading
• Spaced Repetition: Review this content at increasing intervals
• Interleaving: Mix this topic with others during study sessions
• Elaborative Interrogation: Ask yourself why each concept works

Exam Preparation

Practise applying these concepts under timed conditions. Focus on understanding what each question is asking and how marks are allocated. Review examiner reports to learn from common mistakes made by other students.