Biology 20
Explore how living systems function at every scale — from the biochemistry of a single cell to the dynamics of global ecosystems. Biology 20 connects energy, matter, populations, and the human body through Alberta's Program of Studies.
Course Units
Energy and Matter Exchange in the Biosphere
Explore how energy flows through ecosystems and how matter cycles continuously through the biosphere, maintaining equilibrium over time.
Ecosystems and Population Change
Study how species interact within ecosystems, how populations change over time, and how biodiversity shapes living communities across Alberta and the world.
Photosynthesis and Cellular Respiration
Investigate how cells capture light energy, build organic molecules, and extract ATP through photosynthesis and cellular respiration — the complementary engines of life.
Human Systems
Examine the structure, function, and interactions of the major human body systems, from digestion and respiration to circulation, excretion, and defence.
Alberta Curriculum Outcomes
What You Will Learn
Key knowledge and skills from the Alberta Program of Studies — Biology 20
Explain the constant flow of energy through the biosphere, including trophic levels, food chains, and ecological pyramids
Explain the cycling of matter — carbon, oxygen, nitrogen, phosphorus — through biotic and abiotic components of ecosystems
Analyze how energy and matter exchange in the biosphere maintains equilibrium and how humans disrupt this balance
Describe the biotic and abiotic characteristics that define ecosystems and explain species interactions including competition, predation, and symbiosis
Explain the mechanisms involved in population change, including limiting factors, carrying capacity, and population growth models
Describe taxonomy and binomial nomenclature, and classify organisms into the major kingdoms
Explain the mechanisms of natural selection and evaluate evidence supporting evolutionary theory
Investigate photosynthesis: the role of light reactions, the Calvin cycle, and how plants convert solar energy into chemical energy
Investigate cellular respiration: glycolysis, the Krebs cycle, the electron transport chain, and ATP yield from aerobic and anaerobic pathways
Analyze how the structure of organelles (chloroplasts, mitochondria) supports their function in energy transformation
Describe the structure and function of the digestive, respiratory, circulatory, excretory, and immune systems and explain how they interact to maintain homeostasis
Incorporate Indigenous and local knowledge perspectives in understanding living systems and stewardship of Alberta's ecosystems
Attitude Outcomes
Interest in Science
Show curiosity about biology-related questions, issues, and careers, and appreciate science as a dynamic and evolving process of inquiry.
Mutual Respect
Appreciate that scientific understanding is enriched by diverse perspectives, cultures, and knowledge systems, including Indigenous ways of knowing.
Scientific Inquiry
Seek evidence, ask questions, and think critically when exploring biological concepts, experimental results, and real-world biological claims.
Collaboration
Work respectfully and effectively with others when planning investigations, analysing data, and communicating findings in biology.
Stewardship
Demonstrate responsibility toward environmental sustainability, biodiversity conservation, and the long-term health of Alberta's ecosystems.
Safety
Show consistent concern for safety in laboratory and field settings, including proper handling of biological materials and responsible disposal.
Student Resources
How to Study Effectively for Biology 20
Draw the cycles, don't just read them. The carbon, nitrogen, and phosphorus cycles are best learned by drawing them from scratch. If you can reproduce them without looking, you understand them.
Link Unit A and Unit C together. The carbon cycle (Unit A) and photosynthesis/respiration (Unit C) tell the same story at different scales. Recognising CO2 and glucose across both units deepens understanding of both.
Use active recall for vocabulary. Biology 20 has significant terminology. Test yourself with flashcards regularly rather than re-reading definitions — each unit page on this site has flashcards built in.
Trace matter and energy through every system. Ask “where does the energy go?” and “where does the matter go?” in every topic. These two questions connect all four units.
Understand structure-function relationships. Know WHY organelles, organs, and systems are shaped the way they are. Exam questions frequently ask you to connect structure to function.
Use the unit practice tools. Each unit page has a 10–12 question quiz, a matching activity, and flashcards. Use them after every study session — not only before tests.
Teach it out loud. Pick a concept and explain it as if you are teaching it to someone else. Gaps in your explanation show you exactly what to review. This is the most powerful study method.
Practise with past questions. Biology 20 exams emphasise application. Look for questions that give a scenario and ask you to apply a process (e.g., what happens to ATP production if…).