QCE Biology Syllabus Guide (Sciences)

Science understanding

• Compare prokaryotic and eukaryotic cells.
• Identify key organelles and their functions, including the nucleus, mitochondria, rough ER, ribosomes, smooth ER, Golgi apparatus, lysosomes, vacuoles and chloroplasts.
• Describe how stem cells originate through the process of mitosis and differentiate into specialised cells to form tissues.
• Distinguish between unipotent, multipotent, pluripotent and totipotent stem cells.
• Describe how the hierarchical organisation of cells, tissues, organs and systems allow multicellular organisms to obtain nutrients, e.g. digestive and circulatory systems; exchange gases, e.g. respiratory and circulatory systems; remove wastes, e.g. respiratory, circulatory and excretory systems.
• Explain that each body system contains specialised cells and tissues that are structurally suited to function, including size and shape (SA:V ratio) and organelle composition.
• Describe the structure and function of the cell membrane based on the fluid mosaic model, including the role of protein channels, phospholipids, cholesterol and glycoproteins.
• Explain how the cell membrane regulates movement of substances into and out of the cell via osmosis, simple diffusion, facilitated diffusion, protein-mediated active transport, and endocytosis and exocytosis.
• Compare active and passive transport.
• Explain how the size of a cell is limited by surface area-to-volume ratio and rate of diffusion.
• Interpret data from an experiment investigating the effect of surface area-to-volume ratio on the rate of diffusion.

Science as a human endeavour

• Appreciate that to make sense of the complexity of biological systems, scientists often divide them into simpler components that are easier to study, but at each level of the biological hierarchy, new properties emerge.
• Appreciate that pluripotent stem cells have the potential to be grown into specialised cells that can be used to repair or replace ailing organs and tissues. Advances in technology have allowed scientists to reprogram cells to become pluripotent.
• Appreciate that the use of animals in research has played an important role in furthering scientific understanding of the structure and function of multicellular organisms. Ethical treatment of animals as sentient beings has been accepted as a global principle in research and the three strategies of replacement, reduction and refinement form the basis of many international guidelines.

Science inquiry

• Use a light microscope or photographs to view tissues from the respiratory, circulatory, excretory, digestive and/or plant systems; compare epithelial, connective, muscle and nervous tissues; calculate total magnification and field of view.
• Compare organelle composition of different cell types using electron micrographs.
• Investigate the effect of surface area-to-volume ratio on rate of diffusion.
• Explore the safety, ethics and efficacy of stem cell technologies.

Science understanding

• Describe the structure and function of carbohydrates, proteins and lipids.
• Describe the roles of amylase, protease and lipase in chemical digestion.
• Explain how structural features of exchange surfaces in the digestive and circulatory systems of mammals (e.g. villi and capillaries) allow for efficient nutrient exchange.
• Describe how closed circulatory systems facilitate the efficient transport of materials to and from all cells in the body.
• Identify the parts of a nephron and their functions in the production of urine, i.e. glomerulus, Bowman's capsule, proximal tubule, Loop of Henle, distal tubule and collecting duct.
• Explain how glomerular filtration, selective reabsorption and secretion across nephron membranes contribute to the removal of waste.
• Explain how metabolic processes, such as digestion, are controlled and regulated by enzymes.
• Describe the structure and function of enzymes, including the role of the active site.
• Compare the induced-fit and lock-and-key models of enzyme function.
• Explain how enzyme activity is affected by factors such as temperature, pH, presence of inhibitors and substrate concentration.
• Interpret data from an experiment investigating factors affecting enzyme activity.

Science as a human endeavour

• Appreciate how understanding the anatomy and physiology of different body systems allows medical professionals to predict, diagnose, monitor and treat disease.

Science inquiry

• Investigate the effect of temperature/pH/substrate concentration on the reaction rate of different enzymes.
• Explore how understanding enzymes, and their roles in metabolism, can be used to diagnose and treat metabolic disease.

Science understanding

• Distinguish between catabolism and anabolism.
• Explain how ATP allows energy from catabolic reactions to be used in anabolic reactions.
• Describe the process of aerobic respiration, identifying the location in the cell and net inputs and outputs of glycolysis, Krebs cycle and electron transport chain, and the overall reaction (C₆H₁₂O₆ + 6O₂ → 6CO₂ + 6H₂O + 36–38 ATP).
• Compare aerobic and anaerobic respiration.
• Explain how structural features of exchange surfaces in the respiratory and circulatory systems of mammals (alveoli and capillaries) allow for efficient gas exchange.
• Analyse data to predict the direction that materials will be exchanged between alveoli and capillaries, and between capillaries and muscle tissue.
• Describe the process of photosynthesis, identifying the location in the cell and net inputs and outputs of light-dependent reactions, light-independent reactions, and the overall reaction (6CO₂ + 6H₂O + light energy → C₆H₁₂O₆ + 6O₂).
• Compare the structure and function of xylem and phloem tissues.
• Explain how stomata and guard cells facilitate gas exchange in plants.
• Interpret data from an experiment investigating the effect of light intensity, temperature, wind or humidity on the rate of transpiration.

Science as a human endeavour

• Appreciate how scientists use their understanding of natural systems to develop new technologies.

Science inquiry

• Investigate factors affecting the rate of transpiration in different plants, and adaptations that allow for efficient nutrient and/or gas exchange in plants or animals.
• Explore how understanding natural systems can be used to design new technologies, e.g. artificial leaves that convert solar energy into liquid fuel.

Science understanding

• Explain how the nervous and endocrine systems use negative feedback to coordinate responses to internal/external stimuli and maintain homeostasis (stimulus-response model).
• Identify the different types of sensory receptors and their stimuli, including chemoreceptors, thermoreceptors, mechanoreceptors, photoreceptors and nociceptors.
• Describe the structure and function of nerve cells, including dendrites, soma, body, axon, myelin sheath, nodes of Ranvier, axon terminal and synapse.
• Distinguish between sensory neurons, interneurons and motor neurons.
• Explain the passage of a nerve impulse in terms of transmission of an action potential and synaptic transmission, referring to neurotransmitters, receptors, synaptic cleft, vesicles, postsynaptic and presynaptic neurons and signal transduction.
• Describe how hormones relay messages to cells displaying specific receptors via the circulatory or lymphatic system.
• Explain how receptor binding alters cellular activity, recognising that a cell's sensitivity to a specific hormone is directly related to the number of receptors it displays for that hormone.
• Analyse feedback-control diagrams to identify the stimulus, receptor/s, control centre, effector/s and communication pathway/s in different scenarios.
• Explain thermoregulatory mechanisms of endotherms, including structural features (brown adipose tissue, insulation), behavioural responses (kleptothermy, hibernation, aestivation and torpor), and physiological mechanisms (evaporative heat loss, thermogenesis and vasomotor control).
• Explain thermoregulation in humans, including the role of sweating, shivering, vasodilation and vasoconstriction using feedback control diagrams.
• Explain osmoregulation in humans, including the role antidiuretic hormone (ADH) and the kidney using feedback control diagrams.
• Explain how structural and homeostatic mechanisms maintain water balance in plants, including the roles of stomata, vacuoles, cuticle and abscisic acid.
• Interpret data from an experiment comparing the number and distribution of stomata in plants adapted to different environments.

Science as a human endeavour

• Appreciate that living things need to regulate their internal environment so that factors such as pH and temperature are within the tolerance ranges of enzymes that regulate metabolism.
• Appreciate that understanding natural systems can lead to advances in technology and engineering. For example, computer models of human thermoregulation responses, including heat transfer, perspiration, respiration and blood flows, have been developed for use in the design of clothing and environments that aim to protect humans from hyper- and hypothermia.

Science inquiry

• Investigate tolerance limits for water or salt balance on plant growth.
• Investigate structural, behavioural, physiological and/or homeostatic mechanisms used by different species to control heat exchange/metabolic activity/water balance.
• Investigate the use of hormones in agriculture.
• Compare the number and distribution of stomata in plants adapted to different environments.

Science understanding

• Distinguish between infectious and non-infectious disease.
• Identify key features of prions, viruses, bacteria, fungi, protists and parasites.
• Explain how adherence factors, invasion factors, capsules and toxins affect pathogenesis.
• Explain how host cells recognise self from non-self.
• Identify the three lines of defence in vertebrates: the innate immune response (skin and mucous membranes, non-specific), inflammatory response and complement system (non-specific), and adaptive immune response (specific).
• Describe the inflammatory response, including the roles of prostaglandins and vasodilation, neutrophils and macrophages, and natural killer cells.
• Explain the adaptive immune response, including the humoral response (B lymphocytes, antibodies), cell-mediated response (T lymphocytes), and role of memory cells.
• Compare active and passive immunity, both naturally acquired and artificially acquired.
• Interpret long-term immune response data.
• Describe the innate immune responses in plants, including physical defence strategies (barriers and leaf structures) and chemical defence strategies (plant defensins and production of toxins).
• Interpret data from an experiment investigating the effect of an antimicrobial agent on the growth of a microorganism.
• Describe modes of disease transmission, including direct contact, contact with body fluids, contaminated food, contaminated water and disease-specific vectors.
• Explain how the following factors affect the spread of disease: persistence of pathogens within host, transmission mechanism, proportion of the population that are immune or have been immunised, and mobility of individuals in the affected population.
• Explain how personal hygiene measures, contact tracing and quarantine are used to control the spread of disease.
• Analyse data to predict outbreaks, determine the source of an outbreak, infer the mode of disease transmission, and determine the effectiveness of different strategies in controlling the spread of disease.

Science as a human endeavour

• Appreciate that for thousands of years, First Nations peoples' knowledges of natural antiseptics and bush medicines have been used to prevent and treat infections.
• Appreciate that scientific advancement and the development of complex models often requires contribution from multiple individuals across a range of disciplines.
• Appreciate that Australia has an advantage over many other countries because its borders are easier to protect against the influx of disease-carrying materials and organisms. However, as global trade and air travel become more prevalent, it is increasingly important for Australia to protect its agriculture industry and environment through quarantine measures. These include surveillance, monitoring, examination and clearance activities and conform to policies and protocols that are based on scientific data and risk analysis.
• Appreciate that mass vaccination programs are more successful when informed by disease outbreak models.

Science inquiry

• Investigate the effect of an antimicrobial agent on the growth of a microorganism (via the measurement of zones of inhibition) in either a laboratory or virtual context.
• Investigate how the transmission of disease is facilitated by regional and global movement.
• Investigate the effectiveness of health programs for the prevention and eradication of infectious diseases, e.g. smallpox, influenza, polio, Ebola, cholera, malaria.
• Explore how First Nations peoples' knowledges of natural antiseptics and bush medicines are used to prevent and treat infections.
• Explore how the work of scientists such as Rosalyn Sussman Yalow and Peter C Doherty has improved our understanding of infectious disease and the immune response.
• Explore vaccine development.

Science understanding

• Describe genetic, species and ecosystem diversity.
• Describe the biological species concept and identify its limitations.
• Identify the major taxa in the Linnaean system of biological classification and explain how it is used to classify and name species.
• Use dichotomous keys to identify and classify organisms.
• Use the Lincoln index (N = M×n/m) to estimate the size of a population.
• Determine the diversity of species using measures such as species richness, evenness (relative species abundance), percentage cover, percentage frequency and Simpson's diversity index, SDI = 1 – (∑n(n−1)/N(N−1)).
• Describe how sampling can be used to investigate the species diversity of a given area, considering the most appropriate sampling method (random, systematic, stratified), sampling technique (quadrats, line transect, belt-transect, capture-recapture), strategies to minimise bias (size and number of samples, random-number generators, counting criteria, calibrating equipment and noting associated precision), and measure/s of diversity.
• Describe how the distribution and abundance of species in an ecosystem are influenced by biotic factors (food availability, competition for resources, predation, disease) and abiotic factors (space, shelter, availability of water, nutrients, environmental conditions).
• Explain that ecosystems are composed of varied habitats, including microhabitats, which may impact the distribution of species (e.g. uniform, random or clumped), and therefore the validity and reliability of different sampling methods/techniques.
• Interpret data from an experiment investigating how abiotic factors affect the distribution, abundance and/or biodiversity of species in an ecosystem.
• Interpret data to classify and name ecosystems using Specht's classification system and the Holdridge life zone classification scheme.
• Identify and explain different modes of population growth, including exponential growth (J-curve) and logistic growth (S-curve).
• Compare the reproductive strategies and growth curves of K- and r- strategists.
• Calculate population growth rate and change using birth, death, immigration and emigration data.

Science as a human endeavour

• Appreciate that methods of classification are directly related to the purpose for which the data will be used. Hierarchical systems, such as the Linnaean system, can be used to organise, analyse and communicate data about biodiversity. For example, the hierarchical nature of the Linnaean system allows scientists to infer similarities between species; however, as the system was originally based primarily on physical features, the categorisation of species does not always reflect evolutionary relatedness. Species may be re-classified as new information becomes available.
• Appreciate that there are multiple definitions for species, and each has limitations. Examples include the biological species concept, phylogenetic species concept, ecological species concept and morphological species concept.
• Appreciate that developments in software, computing and supercomputing have been important in ecological classification as they have enabled scientists to classify regions according to large sets of biotic and abiotic data and to compare data over time. Supercomputers have also enabled the development of large, complex models to analyse species data collected from multiple individuals in a range of locations, and to infer relationships between species, including their shared evolutionary past.

Science inquiry

• Use the process of stratified sampling to identify different habitats within an ecosystem, investigate changes to abiotic factors in different strata, investigate changes to community composition in different strata (e.g. layers of a forest), infer species interactions within and between strata, and classify an ecosystem.
• Investigate how abiotic factors affect the distribution and/or abundance of species in an ecosystem.
• Investigate changes in species composition along an environmental gradient.
• Investigate how environmental factors affect the global distribution of ecosystems.
• Investigate how the process of classifying ecosystems allows for effective ecosystem management.
• Compare species diversity in two spatially variant ecosystems of the same classification.

Science understanding

• Explain the transfer and transformation of energy as it flows through the biotic components of an ecosystem, including the conversion of light into chemical energy, production of biomass and its interactions with components of the carbon cycle, and loss of energy as heat.
• Analyse food chains, energy flow diagrams and ecological pyramids to determine efficiencies of energy and biomass transfer, gross and net productivity, and loss of energy through radiation, reflection and absorption.
• Describe the transfer and transformation of matter (water, carbon, nitrogen) as it cycles through ecosystems.
• Explain the following species interactions: predation, competition, mutualism, commensalism and parasitism.
• Describe the concept of an ecological niche.
• Explain the competitive exclusion principle.
• Explain the critical role that keystone species play in maintaining the structure of a community.
• Analyse ecological data (e.g. food webs, population data) to identify keystone species, infer species interactions, and predict the outcomes of removing species from an ecosystem.
• Explain how overexploitation, habitat destruction, monocultures and pollution affect community structure and ecosystem functioning.
• Explain how the carrying capacity of an ecosystem can be impacted by changes to biotic and abiotic factors, including climatic events.
• Describe the process of ecological succession.
• Distinguish between primary and secondary succession.
• Identify the features of pioneer species that make them effective colonisers.
• Explain successional changes, with reference to species interactions, abiotic factors, K- and r-selected species, biodiversity and biomass.
• Interpret ecological data to compare ecosystems across spatial and temporal scales.

Science as a human endeavour

• Appreciate that First Nations peoples' knowledges of environmental change and interactions between abiotic and biotic elements of ecosystems has developed over thousands of years and provides valuable data for understanding ecosystem dynamics. This includes knowledge of land management practices that can maintain ecosystems at specific successional points.
• Appreciate that some biologists have advocated for keystone species to be special targets for conservation efforts and keystone species theory has informed many conservation strategies; however, there are differing views about the effectiveness of single-species conservation (such as keystone species, flagship species or umbrella species) in maintaining complex ecosystem dynamics.
• Appreciate that the fossil record and sedimentary rock characteristics provide evidence of past ecosystems.

Science inquiry

• Investigate species interactions, e.g. by looking for correlation in abundance data.
• Investigate the competitive exclusion principle, e.g. by studying vertical zonation on a tree.
• Investigate factors affecting carrying capacity.
• Investigate the effectiveness of single-species conservation in maintaining complex ecosystem dynamics.
• Investigate how the fossil record and sedimentary rock characteristics provide evidence of past ecosystems.
• Explore how First Nations peoples' knowledges of environmental change and interactions between abiotic and biotic elements of ecosystems inform land management practices.

Science understanding

• Describe the structure and function of DNA, genes and chromosomes in prokaryotes and eukaryotes, including helical structure, nucleotide composition (nitrogenous base + sugar + phosphate), complementary base pairing, hydrogen bonds; introns and exons, promoter region; homologous chromosomes (i.e. sister chromatids, centromeres, telomeres, gene loci, alleles), role of histones; circular chromosomes (i.e. prokaryotes, mitochondria, chloroplasts) and plasmids.
• Describe the process of DNA replication with reference to helicase, DNA polymerase and the joining of Okazaki fragments.
• Explain how errors in DNA replication and damage by physical/chemical factors in the environment can lead to point and frameshift mutations.
• Describe the process of meiosis and explain how crossing over, independent assortment and random fertilisation produce variation in the genotypes of offspring.
• Compare spermatogenesis and oogenesis.
• Explain how errors in meiosis can lead to chromosomal abnormalities such as insertions, deletions, duplications, inversions, translocations and aneuploidy.
• Identify ploidy changes within a human karyotype to predict a genetic disorder.
• Explain the process of protein synthesis in terms of transcription of a gene into messenger RNA in the nucleus, RNA processing (5' cap, RNA splicing, poly-A tail), and translation of mRNA into an amino acid sequence at the ribosome, referring to transfer RNA, codons and anticodons.
• Determine the effect of point and frameshift mutations on polypeptides using the genetic code.
• Explain how gene expression is regulated in response to environmental signals and to allow for cell differentiation, including chemical tags that affect chromatin structure (heterochromatin vs. euchromatin) and proteins that bind to the promoter region of a gene (transcription factors).
• Explain how genes from the HOX transcription factor family regulate morphology.
• Describe dominant, recessive, autosomal, sex-linked, polygenic and multiple-allele inheritance.
• Infer patterns of inheritance and predict frequencies of genotypes and phenotypes from genetic data, including histograms (polygenic inheritance), pedigrees (dominant/recessive, autosomal/sex-linked), and Punnett squares (dominant/recessive, autosomal/sex-linked and multiple-allele inheritance).
• Describe the process of making recombinant DNA, including the role of restriction enzymes, plasmids and DNA ligase.
• Describe how PCR and gel electrophoresis are used in DNA profiling and explain how differences in DNA allow for characteristic banding patterns.
• Interpret DNA profiles from gel electrophoresis.

Science as a human endeavour

• Appreciate that the Human Genome Project was an international, collaborative research project which resulted in the publication of the full sequence of the human genome in 2003. The databases associated with the project are freely available via the internet and used extensively by the international scientific community.
• Appreciate that full genome sequencing enables people to identify whether they have certain gene variants, which may enable doctors to structure individualised healthcare programs that will lead to better health; however, there is concern about the risks of making this data available, and the privacy issues regarding ownership and availability of the information.
• Appreciate that a wide range of transgenic crops are currently on the market, some having been engineered to resist pesticides, insects and disease; however, there is concern about the long term ecological impact of releasing engineered organisms into the environment, including the effects on non-target organisms, a speeding of the evolution of pesticide-resistant pest species, and the possibility of gene flow from crop species to weed species resulting in the emergence of 'super weeds'.
• Appreciate that our understanding of genetics and heredity has resulted from collaboration of people from a range of disciplines and continues to develop as new evidence comes to light. Examples of scientists who have advanced our knowledge in this field include Emmanuelle Charpentier and Jennifer A Doudna (genome editing, CRISPR), Elizabeth H Blackburn, Carol W Greider and Jack W Szostak (telomeres), Roger D Kornberg (transcription), Edward B Lewis, Christiane Nusslein-Volhard and Eric F Wieschaus (HOX genes), and Richard J Roberts and Phillip A Sharp (introns and exons).

Science inquiry

• Extract DNA from strawberries, kiwifruit or wheat germ.
• Interpret DNA profiles from gel electrophoresis (laboratory work or computer simulation).
• Investigate the safety and efficacy of gene technologies such as CRISPR and GM crops.
• Investigate how advances in our understanding of genetics/epigenetics are changing the way we prevent, diagnose and/or treat disease.
• Investigate applications of bioinformatics and/or data from the Human Genome Project.
• Explore how the work of different scientists has contributed to our understanding of genetics and heredity.

Science understanding

• Distinguish between microevolution and macroevolution.
• Explain microevolutionary change through the main processes of mutation, gene flow and genetic drift.
• Explain natural selection and identify the three main types of phenotypic selection: stabilising, directional and disruptive.
• Calculate allele frequencies from genotype data.
• Analyse data to determine the effect of a selection pressure on a population, recognising that selection for an allele can be positive or negative.
• Describe how macroevolutionary changes result from the accumulation of microevolutionary changes using examples of divergent, convergent, parallel and coevolution.
• Explain how geographic, temporal and spatial isolation influence gene flow and may lead to allopatric, sympatric and parapatric speciation.
• Explain why populations with reduced genetic diversity face increased risk of extinction.
• Explain how comparative genomics provides evidence for the theory of evolution and how conserved sequences can be used to date divergence.
• Infer species relatedness from cladograms, phylograms and molecular sequence data.
• Determine episodes of evolutionary radiation and mass extinctions from an evolutionary timescale of life on Earth (approximately 3.5 billion years).

Science as a human endeavour

• Appreciate that ICTs such as genetic databases and The Basic Local Alignment Search Tool (BLAST) have allowed large-scale mapping and analysis of DNA and protein sequences. Technological developments in the fields of comparative genomics, comparative biochemistry and bioinformatics have enabled identification of further evidence for evolutionary relationships.
• Appreciate that scientific theories are explanations of the natural world that have been repeatedly tested and corroborated in accordance with the scientific method. Models and theories are contested and refined or replaced when new evidence challenges them, or when a new model or theory has greater explanatory power. Contemporary evidence for evolution comes from palaeontology, biogeography, developmental biology, morphology and genetics.

Science inquiry

• Analyse genotypic changes for a selective pressure in a gene pool (laboratory work or computer simulation).
• Investigate how different selection pressures (e.g. human activities, changes in climate) are affecting evolution.
• Investigate how phylogenetic data is used to track and monitor viruses.
• Investigate the effectiveness of 'green corridors' in maintaining gene flow between populations.
• Investigate how data from palaeontology, biogeography, developmental biology, morphology and/or genetics is used to provide evidence for the theory of evolution.
• Investigate how genomic data is used to track human migration.