VCE Biology: complete 2026 guide to Units 1, 2, 3 and 4 (study design from 2022)

VCE Biology covers four units across Years 11 and 12, sat under the current VCAA study design (from 2022). VCAA lists this design's accreditation as expiring on 31 December 2026, so check vcaa.vic.edu.au for 2027 arrangements. Units 1 and 2 set up the cell, organ systems, inheritance and adaptation. Units 3 and 4 (the Year 12 sequence) deepen into cellular processes, gene expression, immunity and evolution, and produce a VCE study score.

This page is the index. Below you will find every dot-point answer we have for VCE Biology in 2026, organised by unit and area of study, alongside the structural notes you need to plan study.

The four VCE Biology units in 2026

Unit 1: How do organisms regulate their functions

Cell structure and ultrastructure, the plasma membrane, the cell cycle and apoptosis; plant and animal systems including digestive, endocrine and excretory; and adaptations of plants and animals to their environment. Assessed at S/N level only.

Unit 2: How does inheritance impact on diversity

Chromosomes, meiosis and genetic diversity; models of inheritance (autosomal, sex-linked, codominance, incomplete dominance, multiple alleles); pedigrees and crosses; epigenetics; reproductive cloning and genetic screening; DNA manipulation (PCR, gel electrophoresis). Assessed at S/N level only.

Unit 3: How do cells maintain life

Nucleic acid structure and gene expression (transcription, translation); protein structure and function; regulation of gene expression (trp operon); enzymes; photosynthesis and cellular respiration. Two SACs and exam.

Unit 4: How does life change and respond to challenges

Pathogens (cellular and non-cellular); innate and adaptive immune responses; immunological memory and immunity; vaccination and herd immunity; emerging pathogens and the impact of European arrival on Aboriginal and Torres Strait Islander peoples; immunotherapy and monoclonal antibodies; evolution, the fossil record, phylogenetic trees, speciation and human evolution. Two SACs (one is a student-designed scientific investigation) and exam.

Unit 1 dot-point guides

Unit 1 introduces the cell as the basic unit of life and how multicellular plants and animals are organised into specialised systems. The two areas of study assessed for content are:

Area of Study 1: How do cells function?

• Prokaryotic and eukaryotic cells
• Cell size and the surface area to volume ratio
• Cell organelles and the endosymbiotic theory
• Plasma membrane structure and transport
• The cell cycle, mitosis and binary fission
• Apoptosis, disruption to the cell cycle and cancer

Area of Study 2: How do plant and animal systems function?

• Plant cells, tissues and water transport
• Animal cells, tissues, organs and systems (digestive, endocrine, excretory)
• Adaptations of plants and animals to their environment

Area of Study 3 is the Unit 1 student-directed scientific investigation. It is assessed via SAC (a structured research task or report) and is not on the exam. Use the same key science skills you build for Unit 3-4 SACs.

Unit 2 dot-point guides

Unit 2 is the inheritance unit. Chromosomes, meiosis, the rules of inheritance, pedigree analysis, and contemporary DNA techniques.

Area of Study 1: How is inheritance explained?

• Genes, alleles and the genome
• Chromosomes, autosomes, sex chromosomes and karyotypes
• Meiosis, crossing over and genetic diversity
• Models of inheritance (dominant, codominant, incomplete dominance, multiple alleles, sex-linked)
• Pedigree analysis
• Monohybrid crosses and test crosses
• Two-gene crosses: linked and unlinked genes

Area of Study 2: How do inherited adaptations impact on diversity?

• Genes, environment and epigenetics
• Reproductive cloning and genetic screening
• DNA manipulation: PCR and gel electrophoresis

Area of Study 3 is the contemporary bioethical issue investigation. It is assessed via SAC (a structured response to a bioethical case study) and is not on the exam.

Unit 3 dot-point guides

Unit 3 is one of the two assessed Year 12 units. It deepens into the molecular machinery of the cell.

Area of Study 1: What is the role of nucleic acids and proteins in maintaining life?

• Nucleic acids: DNA and RNA structure
• Gene expression: transcription and translation
• Gene regulation: the trp operon
• Protein structure (four levels)
• Enzyme action and rate of reaction

Area of Study 2: How are biochemical pathways regulated?

• Photosynthesis (light-dependent and Calvin cycle)
• Cellular respiration (glycolysis, Krebs cycle, electron transport chain)
• Cell signalling and apoptosis (extension: not in the Unit 3 key knowledge; apoptosis is in Unit 1)

Unit 4 dot-point guides

Unit 4 is the second Year 12 unit. It moves from individual organisms responding to pathogens to populations evolving over time.

Area of Study 1: How do organisms respond to pathogens?

• Pathogens and disease management
• Innate and adaptive immunity

Area of Study 2: How are species related over time?

• Genetic changes and mutation types
• Genetic diversity and recombination
• Evidence for evolution
• Natural selection and evolution
• Speciation
• Human evolution

Area of Study 3 is the Unit 4 student-designed scientific investigation. It is a major SAC, usually presented as a scientific poster.

Exam structure (Units 3 and 4)

The VCE Biology exam is a single paper.

• Duration: 2 hours 30 minutes plus 15 minutes reading time.
• Total marks: 120.
• Section A: about 40 multiple-choice questions for 40 marks.
• Section B: short-answer and extended-response questions for about 80 marks, including data analysis and one or two longer 8-10 mark extended responses.

Both Units 3 and 4 are examined. About half the marks test Unit 3 content and half test Unit 4 content, with some questions integrating across units.

How VCE Biology scales

VCE Biology scales close to the raw study score. In VTAC's 2025 Scaling Report, Biology had a scaled mean of 30.5; a study score of 40 scaled to 41 and a study score of 45 to 46. Biology scales slightly below Chemistry and Physics because its cohort is broader and includes more students without higher-level mathematics. For ATAR planning, run scenarios in the VCE ATAR calculator.

Calculators and tools for Biology

• Monohybrid Punnett square calculator for Unit 2 inheritance problems.
• Dihybrid Punnett square calculator for two-gene crosses.
• Sex-linked (X-linked) inheritance calculator.
• Hardy-Weinberg equilibrium calculator for population genetics.

These are written for HSC Biology but the population genetics, monohybrid and sex-linked calculators map cleanly to VCE Unit 2 and Unit 4 problems.

Study strategy by unit

Units 1 and 2

Build your factual base. Aim for one summary page per area of study with the structures, named examples and the underlying principles. SACs reward clean diagrams and explicit links between structure and function.

Unit 3

This is biochemistry. Master the four levels of protein structure, then enzymes, then photosynthesis and cellular respiration as input-output diagrams. Use our Unit 3 dot-point pages as your active recall checklist.

Unit 4

This is more conceptual. Immunity rewards careful sequencing (first line, second line, third line) and named cell types. Evolution rewards specific named examples (allopatric speciation case studies, hominin species, Out of Africa evidence). Practice past-paper extended responses weekly from Term 3.

The system around VCE Biology

VCE Biology sits inside the wider VCE system. Related explainers:

• How the VCE ATAR is calculated covers VTAC's aggregate and scaling mechanics.
• How VCE study scores work explains the 0-50 scale and per-subject scaling offsets.
• SACs and SATs explained covers internal assessment and moderation.
• VCE exam day: what to actually expect covers logistics and timing.

How to use this hub

If you are starting Unit 1 or 2: work through the AoS 1 dot points first, then AoS 2. The cell biology in Unit 1 is the foundation for everything in Units 3 and 4, so do not skip it.

If you are starting Unit 3 or 4: do the dot-point pages in study-design order. They map one-to-one to VCAA key knowledge. After each one, do one past-paper short-answer question from the past five years.

If you are sitting the exam in three weeks: drill multiple choice from past papers, write one full timed extended-response per area of study, and re-read our VCE exam day guide. Polish what you have; do not start new content.

For the official VCAA Biology Study Design (from 2022) and current past papers, refer to vcaa.vic.edu.au.