Which topic carries the most marks in the VCE Biology external exam?

What is the role of nucleic acids and proteins in maintaining life? carries 25.2% of the marks across the 7 VCAA papers from 2020 to 2025, ahead of How are species related over time? on 22.0%.

How are marks split between question types in the VCE Biology exam?

Short answer carries 66.7% of the marks and multiple choice carries 33.3% of the marks, measured across 7 papers and 840 marks from 2020 to 2025.

Has the topic balance changed in recent VCE Biology papers?

Yes. What is the role of nucleic acids and proteins in maintaining life? moved down 5.7 percentage points, How are species related over time? moved down 5.7 percentage points, How are biochemical pathways regulated? moved up 7.4 percentage points and How is scientific inquiry used to investigate cellular processes and/or biological change? moved up 4.9 percentage points between the 2020 to 2022 and 2023 to 2025 papers.

How many past papers is this VCE Biology analysis based on?

7 VCAA external papers from 2020 to 2025, covering 353 questions and 840 marks. 4.3% of those marks carry no dot-point mapping and sit outside the percentages.

VCE Biology most tested topics

Across the seven VCAA Biology external papers from 2020 to 2025, What is the role of nucleic acids and proteins in maintaining life? carries 25.2% of the marks against 16.3% for How is scientific inquiry used to investigate cellular processes and/or biological change?, so the paper rewards What is the role of nucleic acids and proteins in maintaining life? more than any other topic. At dot-point level 4.3.2.2 carries 4.5% of paper marks, and two of the 57 dot points that the board assesses externally have not appeared in one of these papers. Every percentage below covers the 95.7% of marks that map to a study design dot point.

Computed from 7 VCAA Biology external papers, 2020 to 2025: 353 questions, 519 question parts and 840 marks.

Unit, topic and dot-point shares below are of the 804 marks that map to a dot point, so each of those tables adds to 100%. 156 of the 519 parts are assessed against more than one dot point, and their 282 marks are divided evenly between the dot points they cover.

What these papers are

Year	Exam	Questions	Marks
2025	Exam	50	120
2025	Exam (NHT)	49	120
2024	Exam	50	120
2023	Exam	51	120
2022	Exam	51	120
2021	Exam	51	120
2020	Exam	51	120

Marks by unit

Unit	Share of marks
Unit 4: How does life change and respond to challenges?	58.3%
Unit 3: How do cells maintain life?	41.7%

Marks by topic

Topic	Share of marks	Papers it appears in	Years
What is the role of nucleic acids and proteins in maintaining life?	25.2%	7 of 7	6 of 6
How are species related over time?	22.0%	7 of 7	6 of 6
How do organisms respond to pathogens?	20.0%	7 of 7	6 of 6
How are biochemical pathways regulated?	16.5%	7 of 7	6 of 6
How is scientific inquiry used to investigate cellular processes and/or biological change?	16.3%	7 of 7	6 of 6

Marks by subtopic

Each topic above breaks into the subtopics below, in the same order.

Subtopic	Share of marks	Papers
The relationship between nucleic acids and proteins	14.3%	7 of 7
DNA manipulation techniques and applications	10.8%	7 of 7
Genetic changes in a population over time	7.9%	7 of 7
Human change over time	6.0%	7 of 7
Changes in species over time	4.9%	7 of 7
Determining the relatedness of species	3.2%	7 of 7
Disease challenges and strategies	8.0%	7 of 7
Acquiring immunity	7.3%	7 of 7
Responding to antigens	4.8%	7 of 7
Photosynthesis as an example of biochemical pathways	7.6%	7 of 7
Cellular respiration as an example of biochemical pathways	4.6%	7 of 7
Regulation of biochemical pathways in photosynthesis and cellular respiration	4.3%	7 of 7
Investigation design	8.5%	7 of 7
Scientific evidence	7.4%	7 of 7
Science communication	0.4%	3 of 7

Marks by dot point

Dot-point numbers and wording are VCAA's own. Where a dot point is written as a list, its items run together here separated by semicolons.

Dot point	Content	Topic	Share of marks	Papers
4.3.2.2	ways of organising, analysing and evaluating primary data to identify patterns and relationships including sources of error and uncertainty	How is scientific inquiry used to investigate cellular processes and/or biological change?	4.5%	7 of 7
4.1.2.2	the characteristics and roles of the components of the adaptive immune response against both extracellular and intracellular threats, including the actions of B lymphocytes and their antibodies, helper T and cytotoxic T cells	How do organisms respond to pathogens?	4.3%	7 of 7
4.2.1.1	causes of changing allele frequencies in a population’s gene pool, including environmental selection pressures, genetic drift and gene flow; and mutations as the source of new alleles	How are species related over time?	4.2%	7 of 7
4.3.1.2	characteristics of the selected scientific methodology and method, and appropriateness of the use of independent, dependent and controlled variables in the selected scientific investigation	How is scientific inquiry used to investigate cellular processes and/or biological change?	3.7%	7 of 7
3.1.1.2	the genetic code as a universal triplet code that is degenerate and the steps in gene expression, including transcription, RNA processing in eukaryotic cells and translation by ribosomes	What is the role of nucleic acids and proteins in maintaining life?	3.5%	7 of 7
3.1.2.3	amplification of DNA using polymerase chain reaction and the use of gel electrophoresis in sorting DNA fragments, including the interpretation of gel runs for DNA profiling	What is the role of nucleic acids and proteins in maintaining life?	3.3%	7 of 7
3.1.1.4	the basic elements of gene regulation: prokaryotic trp operon as a simplified example of a regulatory process	What is the role of nucleic acids and proteins in maintaining life?	2.7%	7 of 7
4.1.3.2	scientific and social strategies employed to identify and control the spread of pathogens, including identification of the pathogen and host, modes of transmission and measures to control transmission	How do organisms respond to pathogens?	2.7%	7 of 7
3.2.2.2	the role of Rubisco in photosynthesis, including adaptations of C3, C4 and CAM plants to maximise the efficiency of photosynthesis	How are biochemical pathways regulated?	2.7%	6 of 7
4.2.2.1	changes in species over geological time as evidenced from the fossil record: faunal (fossil) succession, index and transitional fossils, relative and absolute dating of fossils	How are species related over time?	2.6%	6 of 7
3.2.2.1	inputs, outputs and locations of the light dependent and light independent stages of photosynthesis in C3 plants (details of biochemical pathway mechanisms are not required)	How are biochemical pathways regulated?	2.6%	7 of 7
4.3.1.5	the health, safety and ethical guidelines relevant to the selected scientific investigation	How is scientific inquiry used to investigate cellular processes and/or biological change?	2.5%	7 of 7
3.1.2.5	the use of genetically modified and transgenic organisms in agriculture to increase crop productivity and to provide resistance to disease	What is the role of nucleic acids and proteins in maintaining life?	2.5%	7 of 7
4.1.1.2	the innate immune response including the steps in an inflammatory response and the characteristics and roles of macrophages, neutrophils, dendritic cells, eosinophils, natural killer cells, mast cells, complement proteins and interferons	How do organisms respond to pathogens?	2.4%	7 of 7
3.2.2.3	the factors that affect the rate of photosynthesis: light availability, water availability, temperature and carbon dioxide concentration	How are biochemical pathways regulated?	2.4%	7 of 7
3.1.1.7	the role of rough endoplasmic reticulum, Golgi apparatus and associated vesicles in the export of proteins from a cell via the protein secretory pathway	What is the role of nucleic acids and proteins in maintaining life?	2.3%	7 of 7
4.2.2.2	evidence of speciation as a consequence of isolation and genetic divergence, including Galapagos finches as an example of allopatric speciation and Howea palms on Lord Howe Island as an example of sympatric speciation	How are species related over time?	2.3%	6 of 7
3.1.2.4	the use of recombinant plasmids as vectors to transform bacterial cells as demonstrated by the production of human insulin	What is the role of nucleic acids and proteins in maintaining life?	2.2%	5 of 7
4.2.4.3	the human fossil record as an example of a classification scheme that is open to differing interpretations that are contested, refined or replaced when challenged by new evidence, including evidence for interbreeding between Homo sapiens and Homo neanderthalensis and evidence of new putative Homo species	How are species related over time?	2.2%	7 of 7
3.1.1.6	proteins as a diverse group of molecules that collectively make an organism’s proteome, including enzymes as catalysts in biochemical pathways	What is the role of nucleic acids and proteins in maintaining life?	2.2%	7 of 7

These 20 dot points carry 57.8% of the paper marks between them. Another 35 assessed dot points share the rest, and 2 of the 57 externally assessable dot points have not been assessed in any of these 7 papers. Content that has not appeared is still examinable.

What has moved between papers

Comparing the 2020 to 2022 papers with the 2023 to 2025 papers, four topics have moved by more than 3.0 percentage points.

Topic	2020 to 2022 share	2023 to 2025 share	Movement
What is the role of nucleic acids and proteins in maintaining life?	28.5%	22.8%	down 5.7 points
How are species related over time?	25.4%	19.7%	down 5.7 points
How are biochemical pathways regulated?	12.2%	19.6%	up 7.4 points
How is scientific inquiry used to investigate cellular processes and/or biological change?	13.4%	18.3%	up 4.9 points

How the papers are built

Short answer carries 66.7% of the marks across these 7 papers.

Question type	Share of marks	Marks	Parts
Short answer	66.7%	560	239
Multiple choice	33.3%	280	280

Verb	Share of marks	Marks	Parts
explain	18.2%	153	58
describe	10.1%	85	34
justify	8.1%	68	27
outline	7.1%	60	22
identify	6.3%	53	23
state	5.7%	48	23
discuss	2.6%	22	6
compare	2.3%	19	5

What these percentages do not tell you

Where to practise

Every topic above links to its own page of real VCAA questions with marking criteria and average scores attached: What is the role of nucleic acids and proteins in maintaining life?, How are species related over time?, How do organisms respond to pathogens?, How are biochemical pathways regulated? and How is scientific inquiry used to investigate cellular processes and/or biological change?. For how students actually score on this content, read VCE Biology hardest topics, and for the full question bank start at VCE Biology.

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