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BIOLOGY · HKDSE

BIOLOGY/21

(Elective Part - any 2 of 4 electives)

Biology · 2017 · Variant 1

Relative difficulty

Standard

Analysis source: Hong Kong Examinations and Assessment Authority (HKEAA)

Analysis aligned to the official syllabus and assessment design.

Relative difficulty

Cohort performance

Session statistics from official examination reports

No data available in official reports

Key examiner messages

Top priorities from the principal examiner before you revise

No data available in official reports

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

No data available in official reports

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

No data available in official reports

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

No data available in official reports

Deep insights

What top candidates did

Techniques and approaches examiners rewarded in this series

No data available in official reports

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

No data available in official reports

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

LowHigh
Topic
2021
2022
2023
2024
2025
Σ

Essential life processes in animals

18
14
13
22
67

Essential life processes in plants

20
15
19
54

Biodiversity and evolution

16
15
31

Human impact on the environment

20
11
31

Ecosystems

17
11
28

Cellular energetics

16
16

Basic genetics

14
14

Molecular genetics

11
11

Difficulty trend

How session difficulty has shifted across recent years

20212022202320242025
2021 2021 · 3.0/52022 2022 · 3.5/52023 2023 · 3.8/52024 2024 · 3.8/52025 2025 · 3.8/5

Paper comparison

Marks and duration breakdown across papers in this session

No data available in official reports

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

No data available in official reports

Self-diagnostic checklist

Key actions before you sit this paper — copy and tick off as you revise

No data available in official reports

Teacher briefing pack

One-page session summary for tutors and classroom review

No data available in official reports

Exam tips

Paper format

Duration
1h
Total marks
40

Analysis is paraphrased for study purposes. Always verify against the official examiner report and mark scheme.

BIOLOGY/21 — HKDSE Biology (2017) | Revui