Wales Β· WJECSyllabus
Combined Science syllabus, dot point by dot point
Every dot point in the Wales Combined Sciencesyllabus, with a focused answer for each one. Click any dot point for a worked explainer, past exam questions, and links to related dot points. Written by Claude Opus 4.8, Anthropic's latest AI.
Unit 1 Biology 1: Cells and respiration
Module overview β- What is respiration, and how do aerobic and anaerobic respiration differ in humans and microorganisms?Respiration as the release of energy from glucose, the word and symbol equations for aerobic respiration, anaerobic respiration in muscles and in yeast (fermentation), and a comparison of the two.9 min answer β
- What are the parts of animal and plant cells, and how are cells organised into tissues and organs?Animal and plant cell structure and the function of each part, the differences between plant and animal cells, and how cells are organised into tissues, organs and organ systems.9 min answer β
- How do substances move into and out of cells by diffusion, osmosis and active transport?Diffusion, osmosis and active transport as ways substances cross cell membranes, the factors affecting diffusion, the effect of osmosis on cells, and the osmosis required practical.10 min answer β
- How are cells specialised for their jobs, and how do we use a microscope to see and measure them?How named cells are adapted to their functions, the use of a light microscope to view cells, and calculating magnification and real size using the magnification equation.9 min answer β
- How is the human breathing system built, and how are the alveoli adapted for gas exchange?The structure of the human breathing system, the mechanism of ventilation, and how the alveoli are adapted for efficient gas exchange by diffusion.9 min answer β
Unit 1 Biology 1: Digestion and circulation
Module overview β- How is the small intestine adapted to absorb digested food efficiently?Absorption of the soluble products of digestion in the small intestine, and how the villi are adapted for efficient absorption.9 min answer β
- What are the parts of blood, and how does coronary heart disease affect the heart?The components of blood and their functions, and the cause and treatment of coronary heart disease.9 min answer β
- Which enzymes digest each food group, and how do we test foods for starch, sugar, protein and fat?The action of carbohydrase, protease and lipase enzymes, the products of digestion, and the food tests for starch, reducing sugar, protein and fat.10 min answer β
- What are the organs of the digestive system, and what does each one do?The organs of the human digestive system and their functions, the role of mechanical and chemical digestion, and the action of bile.9 min answer β
- How is the heart built, and how do the blood vessels move blood around the double circulation?The structure of the heart, the double circulatory system, and the structure and function of arteries, veins and capillaries.9 min answer β
Unit 1 Biology 1: Plants and ecosystems
Module overview β- How does energy flow through a food chain, and why are food chains short?Food chains, food webs and trophic levels, pyramids of biomass, and the transfer and loss of energy and biomass between trophic levels.9 min answer β
- How is a leaf adapted for photosynthesis, and how do xylem and phloem transport substances in a plant?The structure of a leaf and how it is adapted for photosynthesis and gas exchange, and the transport of water and food in the xylem and phloem.9 min answer β
- How do plants make food by photosynthesis, and what limits the rate of the reaction?Photosynthesis as the process that makes glucose using light, the word and symbol equations, the factors that limit the rate of photosynthesis, and the related required practical.10 min answer β
- How are carbon and nitrogen recycled through ecosystems, and what role do microorganisms play?The carbon cycle and the nitrogen cycle, the role of decomposers and named bacteria, and how human activity affects these cycles and biodiversity.9 min answer β
- What is transpiration, and which factors change the rate at which a plant loses water?Transpiration as the loss of water vapour from a plant, the transpiration stream, and the factors affecting the rate of transpiration.9 min answer β
Unit 4 Biology 2: Cells, genetics and evolution
Module overview β- How do cells divide by mitosis and meiosis, and what are stem cells used for?Cell division by mitosis and meiosis, the differences between them, and stem cells and their uses.9 min answer β
- How are living things classified, and why does biodiversity matter?The classification of living things into groups, the use of keys to identify organisms, and the importance of biodiversity.9 min answer β
- What is DNA, and how are characteristics inherited through dominant and recessive alleles?DNA, genes and chromosomes, dominant and recessive alleles, and using genetic diagrams to predict the inheritance of a characteristic.10 min answer β
- What causes variation, and how does natural selection lead to evolution?Genetic and environmental variation, the theory of evolution by natural selection, and the evidence for evolution.9 min answer β
Unit 4 Biology 2: Microorganisms and disease
Module overview β- How are microorganisms grown safely in the lab, and how is aseptic technique used?Culturing microorganisms on agar, the use of aseptic technique to avoid contamination, and the related practical.9 min answer β
- How does the body defend itself against pathogens?The body's defences against pathogens, including physical and chemical barriers and the role of white blood cells.9 min answer β
- What are pathogens, and how are communicable diseases spread and prevented?Pathogens as disease-causing microorganisms, the types of pathogen, how communicable diseases spread, and how their spread is reduced.9 min answer β
- How do vaccines give immunity, and what do antibiotics treat?How vaccination produces immunity, how antibiotics treat bacterial infections, and the problem of antibiotic resistance.9 min answer β
Unit 4 Biology 2: Response and regulation
Module overview β- What is homeostasis, and how does the body keep its temperature steady?Homeostasis as keeping a constant internal environment, and how body temperature is controlled by the skin.9 min answer β
- What are hormones, and how is blood glucose controlled by insulin?Hormones as chemical messengers, the control of blood glucose by insulin, and diabetes.9 min answer β
- How does the eye detect light, and how does it focus on near and distant objects?The structure of the eye and the function of its parts, how the eye focuses light (accommodation), and the pupil reflex.9 min answer β
- How does the nervous system carry information, and how does a reflex protect the body?The structure of the nervous system, the pathway of a nervous impulse, and the reflex arc as a fast automatic response.9 min answer β
Unit 2 Chemistry 1: Rate of chemical change
Module overview β- How do temperature, concentration, surface area and catalysts change the rate of a reaction?The effects of temperature, concentration, pressure, surface area and catalysts on the rate of reaction, explained by collision theory.9 min answer β
- How do we measure the rate of a reaction and interpret a rate graph?Methods of measuring rate by gas volume, mass loss or a colour change, the required practical, and interpreting rate graphs.9 min answer β
- What is the rate of a reaction, and how does collision theory explain it?The rate of reaction as how fast reactants are used or products form, and collision theory in terms of frequency and energy of collisions.9 min answer β
Unit 2 Chemistry 1: Substances and atomic structure
Module overview β- What is inside an atom, and how do isotopes give an element its relative atomic mass?Sub-atomic particles and their relative masses and charges, working out particle numbers from atomic and mass number, isotopes, and calculating relative atomic mass.9 min answer β
- How do we write word and balanced symbol equations, and why is mass conserved in a reaction?Word and balanced symbol equations with state symbols, the law of conservation of mass, and explaining apparent mass changes.10 min answer β
- How are electrons arranged in shells, and how does this link to the Periodic Table?How electrons fill shells, the electronic structures of the first twenty elements, and linking outer electrons to group and shells to period.9 min answer β
- What is the difference between an element, a compound and a mixture, and how do we tell a chemical reaction has happened?Classifying substances as elements, compounds or mixtures, reading chemical formulae, and distinguishing physical changes from chemical reactions.9 min answer β
- How is the Periodic Table arranged, and what are the trends in Groups 1, 7 and 0?The arrangement of the Periodic Table into groups and periods, metals and non-metals, and the trends in reactivity in Group 1, Group 7 and Group 0.9 min answer β
Unit 2 Chemistry 1: The Earth and its resources
Module overview β- How do greenhouse gases cause climate change, and what pollutants come from burning fuels?The greenhouse effect and human causes of climate change, the products of combustion, and the pollutants from burning fuels and their effects.9 min answer β
- What is the limestone cycle, and how is limestone used to make useful materials?Thermal decomposition of limestone, the reactions of the limestone cycle, and the uses of limestone, quicklime, slaked lime and cement.9 min answer β
- What is the atmosphere made of today, and how did it change over the Earth's history?The composition of the present-day atmosphere and how the early atmosphere changed, including the roles of oceans, plants and the early volcanic atmosphere.9 min answer β
- How is drinking water made safe, and what does it mean for a substance to be soluble?The treatment of water to make it safe to drink, the testing of water purity, and solubility including the idea of saturated solutions.9 min answer β
Unit 5 Chemistry 2: Acids, metals and energy
Module overview β- What are acids and bases, and what does the pH scale tell us?Acids, bases and alkalis, the pH scale and indicators, and neutralisation as a reaction between an acid and a base.9 min answer β
- What is electrolysis, and how is it used to extract aluminium?Electrolysis as the breakdown of an ionic compound using electricity, the products at the electrodes, and the extraction of aluminium.9 min answer β
- What are exothermic and endothermic reactions, and how are they shown on a reaction profile?Exothermic and endothermic reactions, examples of each, and reaction profile diagrams showing activation energy.9 min answer β
- What do acids react with, and how is a soluble salt prepared?The reactions of acids with metals, bases and carbonates, the salts produced, and how to prepare a soluble salt.9 min answer β
- How are metals ordered by reactivity, and how does this decide how a metal is extracted?The reactivity series, displacement reactions, and how the method of extracting a metal depends on its reactivity.9 min answer β
Unit 5 Chemistry 2: Bonding and properties
Module overview β- How does covalent bonding work, and why do simple molecular substances have low melting points?Covalent bonding as the sharing of electrons between non-metals, simple molecular substances, and their properties.9 min answer β
- What are giant covalent and metallic structures, and how does metallic bonding explain the properties of metals?Giant covalent structures such as diamond and graphite, metallic bonding, and how each structure explains the properties of the substance.9 min answer β
- How does ionic bonding form, and why do ionic compounds have their properties?Ionic bonding as the transfer of electrons between metals and non-metals, the formation of ions, and the properties of ionic compounds.9 min answer β
- How can we work out the type of bonding in a substance from its properties?Linking the type of structure and bonding to the properties of a substance, and using properties to identify the bonding type.9 min answer β
Unit 5 Chemistry 2: Organic and industrial chemistry
Module overview β- What are alkanes and alkenes, and why is cracking used?Alkanes and alkenes, the test for an alkene, the combustion of hydrocarbons, and cracking to make smaller useful molecules.9 min answer β
- What is crude oil, and how is it separated into useful fractions?Crude oil as a mixture of hydrocarbons, fractional distillation, and the properties and uses of the fractions.9 min answer β
- What is a reversible reaction, and what does equilibrium mean?Reversible reactions, the symbol used, energy changes in reversible reactions, and the idea of a dynamic equilibrium in a closed system.9 min answer β
- How is ammonia made in the Haber process, and why are the conditions chosen?The Haber process for making ammonia, the conditions used, and why these conditions are a compromise.9 min answer β
Unit 3 Physics 1: Electricity and the grid
Module overview β- What are current, potential difference and resistance, and how are they related?Electric current, potential difference and resistance, the equation V = IR, and the current-voltage graphs for a resistor, a filament lamp and a diode.9 min answer β
- How does mains electricity work in the home, and how do fuses and earthing keep us safe?Mains alternating current, the live, neutral and earth wires in a plug, the dangers of electricity, and how fuses, circuit breakers and earthing provide safety, with the power equation.9 min answer β
- How is electricity generated, and how do transformers change the voltage?Electromagnetic induction in a generator, how a transformer changes voltage, and the difference between step-up and step-down transformers.9 min answer β
- How do current, potential difference and resistance behave in series and parallel circuits?The rules for current and potential difference in series and parallel circuits, and how resistance combines in each.9 min answer β
- How does the National Grid carry electricity efficiently across the country?The structure of the National Grid and why electricity is transmitted at high voltage to reduce energy loss.8 min answer β
Unit 3 Physics 1: Energy resources and efficiency
Module overview β- What are the renewable and non-renewable energy resources, and how do power stations generate electricity?Renewable and non-renewable energy resources, how power stations generate electricity, and the advantages and disadvantages of different resources.9 min answer β
- How is energy transferred and stored, and how do we calculate efficiency?Energy stores and transfers, the conservation of energy, wasted energy, and calculating efficiency.9 min answer β
- How is heat transferred from a house, and how can we reduce these energy losses?Heat transfer by conduction, convection and radiation, and methods of reducing energy loss from a house such as insulation.9 min answer β
Unit 3 Physics 1: Waves
Module overview β- What are the features of a wave, and how are wave speed, frequency and wavelength related?Transverse and longitudinal waves, the features of a wave (amplitude, wavelength, frequency, period), and the wave equation.9 min answer β
- How do waves reflect and refract, and why does refraction happen?The reflection of waves and the law of reflection, and the refraction of waves as they change speed when crossing a boundary.9 min answer β
- What is the electromagnetic spectrum, and what are the uses and dangers of each type of wave?The electromagnetic spectrum in order, its common properties, and the uses and dangers of each type of electromagnetic wave.9 min answer β
- What is total internal reflection, and how is it used in optical fibres?Total internal reflection, the critical angle, and the use of total internal reflection in optical fibres and prisms.8 min answer β
Unit 6 Physics 2: Forces and motion
Module overview β- How are speed and acceleration calculated, and how do we read motion graphs?Speed and average speed, acceleration, and interpreting distance-time and velocity-time graphs.9 min answer β
- How do forces affect motion, and what does F = ma tell us?Balanced and unbalanced (resultant) forces, Newton's laws of motion, and the equation force equals mass times acceleration.9 min answer β
- What affects the stopping distance of a car, and how do safety features protect us?Thinking, braking and stopping distances, the factors that affect them, and how vehicle safety features reduce injury.9 min answer β
- How are work, power, kinetic and potential energy calculated?Work done, power, kinetic and gravitational potential energy, and the conservation of energy in mechanical situations.9 min answer β
Unit 6 Physics 2: Kinetic theory
Module overview β- What causes gas pressure, and how does it change with temperature and volume?Gas pressure in terms of particle collisions, and how pressure changes with temperature and with volume.9 min answer β
- How does the particle model explain the three states of matter and changes of state?The particle model of solids, liquids and gases, density, and changes of state as physical changes.9 min answer β
- What is specific heat capacity, and what happens to energy during a change of state?Specific heat capacity and the equation for energy, internal energy, and the energy needed for a change of state.9 min answer β
Unit 6 Physics 2: Space and radioactivity
Module overview β- What is half-life, and how is it used to work out how much of a source remains?Half-life as the time for the activity to halve, calculating remaining activity, and uses such as dating and medicine.9 min answer β
- What are nuclear fission and fusion, and how do they release energy?Nuclear fission and the chain reaction in a reactor, nuclear fusion in stars, and the difference between them.9 min answer β
- What is in the Solar System, and what keeps the planets in orbit?The structure of the Solar System, the role of gravity in orbits, and how a star is formed and stays stable.9 min answer β
- What are alpha, beta and gamma radiation, and how do they differ?Radioactive decay, the properties of alpha, beta and gamma radiation, their penetrating power, and the dangers and uses of radiation.9 min answer β
Unit 7: Practical and enquiry skills
Module overview β- How do you analyse results with a graph and evaluate an investigation?Analysing results: plotting and interpreting graphs, drawing a conclusion, and evaluating the reliability and validity of an investigation.9 min answer β
- How do you take and record measurements accurately in a practical?Carrying out an investigation: choosing apparatus, taking accurate and precise measurements, repeating readings, and recording results in a table.9 min answer β
- How do you plan a fair scientific investigation?Planning an investigation: the independent, dependent and control variables, a hypothesis, a fair test, and risk assessment.9 min answer β