BIOLOGY · Common Test for University Admissions (大学入学共通テスト)
BIOLOGY/11
Biology
Biology · 2023 · Variant 1
Relative difficulty
Analysis source: National Center for University Entrance Examinations (DNC)
Analysis aligned to the official syllabus and assessment design.
4.0 / 5
100
60 min
Genetics/data interpretation and physiology regulation are especially high-yield, with many items built around experiments, pedigrees, graphs or feedback mechanisms.
Cohort performance
Session statistics from official examination reports
Total marks
100
Duration
60 min
Session difficulty
4.0 / 5
Calculator policy
Scientific calculators permitted only where specified in the DNC implementation guidelines; programming functions and CAS are prohibited. En
Key examiner messages
Top priorities from the principal examiner before you revise
生物 covers cells and molecules, metabolism, genetics, evolution, reproduction and development, homeostasis, environmental responses, ecosystems and biodiversity. R7 Common Test biology emphasizes interpreting experiments and data, explaining mechanisms and reasoning from eviden…
Biology is 60 minutes/100 marks alone, or part of a 130-minute/200-mark two-science sitting.
Official reports emphasize inquiry and data use; practise reading unfamiliar experiments before memorizing extra terminology.
For monohybrid crosses, expected genotype ratio from Aa x Aa is 1:2:1 and phenotype ratio is 3:1 under complete dominance.
The DNC Problem Evaluation Committee publishes per-subject reports after each January session, rating alignment with the Course of Study (学習指導要領), item difficulty balance, and whether items discriminate without exceeding syllabus scope.
Question difficulty map
How candidates performed on each question in this series
No data available in official reports
Assessment objectives
Skill and AO weighting from official examiner commentary
Skill weighting
Cognitive skills emphasised in official test design.
Data and experiment interpretation
Weight: 36100%Conceptual mechanism reasoning
Weight: 2878%Genetic and quantitative reasoning
Weight: 2056%Systems comparison
Weight: 1644%
Method marks watchlist
Where working, steps, or method marks were commonly lost
No data available in official reports
Recurring mistakes across years
Themes examiners flag in multiple recent sessions for this subject
Experimental design: Accepting a conclusion when the control condition is missing or insufficient. — Check what changed, what was held co…
Genetics: Assuming dominance from frequency alone. — Use pedigree pattern, parent-child relationships and genotype possibilities.
Homeostasis: Confusing sensor, control center and effector roles. — Label each component in the feedback loop before reading options.
Evolution: Saying individuals evolve because they need to adapt. — State that allele frequencies in populations change through selection …
Ecology: Treating energy and matter cycles as the same process. — Energy flows and is lost as heat; matter cycles through reservoirs.
Question choice intelligence
Mean scores and popularity for optional questions (HKDSE electives)
No data available in official reports
Level exemplars
What candidate scripts at each grade level looked like
No data available in official reports
Grade & admission context
How marks relate to grade thresholds and entry standards
Official body
National Center for University Entrance Examinations (DNC)
Grading system
Full science subjects are scored 0–100 raw; universities use deviation values (偏差値)
Scale band
0–100 raw
Scale band
Deviation 50 = mean
Scale band
University cut-off
Deep insights
What top candidates did
Techniques and approaches examiners rewarded in this series
Read experiments like arguments
Identify hypothesis, manipulation, control, measurement and conclusion. Ask whether the data actually excludes alternative explanations.
Draw genetic crosses
For inheritance, write genotypes, gametes and phenotype ratios. For pedigrees, mark affected/unaffected, sex, generation and whether the trait skips generations.
Use regulation loops
For hormones, nerves and homeostasis, draw stimulus -> receptor -> control center -> effector -> response. Negative feedback is a frequent pattern.
Connect structure to function
When studying organelles, enzymes, membranes, organs or ecosystems, pair each structure with what it enables and what happens if it changes.
Quantify ecology
Population growth, energy flow, biomass pyramids and diversity indices require ratios and percentages. Read whether the question asks number, rate or density.
Compare evolutionary explanations
Distinguish mutation, recombination, natural selection, genetic drift, gene flow and isolation. The correct explanation must fit the evidence scale.
Command word playbook
How to match each command word to the expected response style
No data available in official reports
Time traps
Sections where candidates spent disproportionate time relative to marks
No data available in official reports
Syllabus traceability
Topics linked to questions and mark weighting in this session
Cells, molecules, metabolism and gene expression
Official topic weighting
Genetics, reproduction, development and evolution
Official topic weighting
Homeostasis, response and physiology
Official topic weighting
Ecology, biodiversity and environmental biology
Official topic weighting
MCQ trap analytics
Commonly chosen wrong options from examiner commentary
No data available in official reports
Topic heatmap across years
Mark concentration by topic and exam year for this subject
Mark intensity
Cells, molecules, metabolism and gene expression
Genetics, reproduction, development and evolution
Homeostasis, response and physiology
Ecology, biodiversity and environmental biology
Difficulty trend
How session difficulty has shifted across recent years
Paper comparison
Marks and duration breakdown across papers in this session
Biology: for one science subject / for two science subjects Cells, genetics, physiology, evolution, ecology, experiments and data sources
Marks you can still earn
Where valid approaches outside the mark scheme may still gain credit
No data available in official reports
Practise what examiners flagged
Target weak topics from this report inside the Revui app
Cells, molecules, metabolism and gene expression
Official topic weighting
Practise in RevuiGenetics, reproduction, development and evolution
Official topic weighting
Practise in RevuiHomeostasis, response and physiology
Official topic weighting
Practise in RevuiEcology, biodiversity and environmental biology
Official topic weighting
Practise in RevuiSelf-diagnostic checklist
Key actions before you sit this paper — copy and tick off as you revise
- 1Message
生物 covers cells and molecules, metabolism, genetics, evolution, reproduction and development, homeostasis, environmental responses, ecosystems and biodiversity. R7 Common Test biology emphasizes interpreting experiments and data, explaining mechanisms and reasoning from eviden…
- 2Message
Biology is 60 minutes/100 marks alone, or part of a 130-minute/200-mark two-science sitting.
- 3Message
Official reports emphasize inquiry and data use; practise reading unfamiliar experiments before memorizing extra terminology.
- 4Message
For monohybrid crosses, expected genotype ratio from Aa x Aa is 1:2:1 and phenotype ratio is 3:1 under complete dominance.
- 5Message
The DNC Problem Evaluation Committee publishes per-subject reports after each January session, rating alignment with the Course of Study (学習指導要領), item difficulty balance, and whether items discriminate without exceeding syllabus scope.
- 6Pitfall
Experimental design: Accepting a conclusion when the control condition is missing or insufficient. — Check what changed, what was held co…
- 7Pitfall
Genetics: Assuming dominance from frequency alone. — Use pedigree pattern, parent-child relationships and genotype possibilities.
- 8Pitfall
Homeostasis: Confusing sensor, control center and effector roles. — Label each component in the feedback loop before reading options.
- 9Pitfall
Evolution: Saying individuals evolve because they need to adapt. — State that allele frequencies in populations change through selection …
- 10Pitfall
Ecology: Treating energy and matter cycles as the same process. — Energy flows and is lost as heat; matter cycles through reservoirs.
- 11Strength
Read experiments like arguments: Identify hypothesis, manipulation, control, measurement and conclusion. Ask whether the data actuall
- 12Strength
Draw genetic crosses: For inheritance, write genotypes, gametes and phenotype ratios. For pedigrees, mark affected/unaffec
- 13Strength
Use regulation loops: For hormones, nerves and homeostasis, draw stimulus -> receptor -> control center -> effector -> res
Teacher briefing pack
One-page session summary for tutors and classroom review
2023 2023
Biology
生物 covers cells and molecules, metabolism, genetics, evolution, reproduction and development, homeostasis, environmental responses, ecosystems and biodiversity. R7 Common Test biology emphasizes interpreting experiments and data, explaining mechanisms and reasoning from evidence
生物 covers cells and molecules, metabolism, genetics, evolution, reproduction and development, homeostasis, environmental responses, ecosystems and biodiversity. R7 Common Test biology emphasizes interpreting experiments and data, explaining mechanisms and reasoning from eviden…
Biology is 60 minutes/100 marks alone, or part of a 130-minute/200-mark two-science sitting.
Official reports emphasize inquiry and data use; practise reading unfamiliar experiments before memorizing extra terminology.
Experimental design: Accepting a conclusion when the control condition is missing or insufficient. — Check what changed, what was held co…
Genetics: Assuming dominance from frequency alone. — Use pedigree pattern, parent-child relationships and genotype possibilities.
- Total marks
- 100
- Duration
- 60 min
- Session difficulty
- 4.0 / 5
- Calculator policy
- Scientific calculators permitted only where specified in the DNC implementation guidelines; programming functions and CAS are prohibited. En
Session analysis
生物 covers cells and molecules, metabolism, genetics, evolution, reproduction and development, homeostasis, environmental responses, ecosystems and biodiversity. R7 Common Test biology emphasizes interpreting experiments and data, explaining mechanisms and reasoning from evidence rather than memorizing terms alone. National Center for University Entrance Examinations (DNC) emphasises genetics/data interpretation and physiology regulation are especially high-yield, with many items built around experiments, pedigrees, graphs or feedback mechanisms.. Priority revision: Cells, molecules, metabolism and gene expression, Genetics, reproduction, development and evolution, Homeostasis, response and physiology, Ecology, biodiversity and environmental biology. Identify hypothesis, manipulation, control, measurement and conclusion. Ask whether the data actually excludes alternative explanations.
Updated 2026-07-03
Paper breakdown
Biology: for one science subject / for two science subjects Cells, genetics, physiology, evolution, ecology, experiments and data sources
Top chapters
Exam structure insights
Marks by syllabus topic
Revision priority from official test-design weighting.
Mark accessibility
Estimated difficulty spread based on official design.
Genetics/data interpretation and physiology regulation are especially high-yield
Paper structure
Official paper breakdown for this subject.
Biology
100·10·100%
Official syllabus scope
生物 covers cells and molecules, metabolism, genetics, evolution, reproduction and development, homeostasis, environmental responses, ecosystems and biodiversity. R7 Common Test biology emphasizes interpreting experiments and data, explaining mechanisms and reasoning from evidence rather than memorizing terms alone.
Difficulty verdict
Rated 4/5 for January sessions. Genetics/data interpretation and physiology regulation are especially high-yield, with many items built around experiments, pedigrees, graphs or feedback mechanisms.
What examiners measure
1. Explain biological structures and processes from molecular to ecosystem scale. 2. Interpret experimental design, graphs, tables, pedigrees and microscopy images. 3. Apply genetics, evolution and physiology concepts to unfamiliar data. 4. Infer mechanisms from evidence and evaluate hypotheses. 5. Connect biological systems through regulation, interaction and adaptation.
Where the marks are
Highest-weight syllabus areas: Cells, molecules, metabolism and gene expression; Genetics, reproduction, development and evolution; Homeostasis, response and physiology; Ecology, biodiversity and environmental biology.
Examiner notes & key calculations
- Biology is 60 minutes/100 marks alone, or part of a 130-minute/200-mark two-science sitting.
- Official reports emphasize inquiry and data use; practise reading unfamiliar experiments before memorizing extra terminology.
- For monohybrid crosses, expected genotype ratio from Aa x Aa is 1:2:1 and phenotype ratio is 3:1 under complete dominance.
- Pedigree analysis should test autosomal dominant, autosomal recessive, X-linked and mitochondrial patterns against every generation.
- Enzyme activity graphs usually depend on temperature, pH, substrate concentration or inhibitor type; identify which variable changes.
- Homeostasis questions often ask the direction of response: if blood glucose rises, insulin promotes uptake/storage and lowers it.
- Ecology calculations may use growth rate, carrying capacity, trophic efficiency or population density; write formula and units.
- Paper 1: Biology · 100 marks · 60 min for one science subject / 130 min for two science subjects · Cells, genetics, physiology, evolution, ecology, experiments and data sources.
Exam tips
Paper format
- Duration
- 60 min for one science subject / 130 min for two science subjects
- Total marks
- 100
- Weighting
- 100%
- Question types
- Cells, genetics, physiology, evolution, ecology, experiments and data sources
- Identify hypothesis, manipulation, control, measurement and conclusion. Ask whether the data actually excludes alternative explanations.
- For inheritance, write genotypes, gametes and phenotype ratios. For pedigrees, mark affected/unaffected, sex, generation and whether the trait skips generations.
- For hormones, nerves and homeostasis, draw stimulus -> receptor -> control center -> effector -> response. Negative feedback is a frequent pattern.
Common mistakes
Experimental design
Accepting a conclusion when the control condition is missing or insufficient.
How to avoid: Check what changed, what was held constant and what was measured.
Genetics
Assuming dominance from frequency alone.
How to avoid: Use pedigree pattern, parent-child relationships and genotype possibilities.
Homeostasis
Confusing sensor, control center and effector roles.
How to avoid: Label each component in the feedback loop before reading options.
Analysis is paraphrased for study purposes. Always verify against the official examiner report and mark scheme.