Back to Wales Combined Science
Wales · WJECQ&A
Combined ScienceQ&A by dot point
A short Q&A bank for every Wales Combined Science syllabus dot point. Each question and answer is drawn directly from our worked dot-point page, so you can scan key concepts before opening the long-form answer.
Unit 1 Biology 1: Cells and respiration
- 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.2Q&A pairs
- 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.2Q&A pairs
- 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.2Q&A pairs
- 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.2Q&A pairs
- The structure of the human breathing system, the mechanism of ventilation, and how the alveoli are adapted for efficient gas exchange by diffusion.2Q&A pairs
Unit 1 Biology 1: Digestion and circulation
- Absorption of the soluble products of digestion in the small intestine, and how the villi are adapted for efficient absorption.2Q&A pairs
- The components of blood and their functions, and the cause and treatment of coronary heart disease.2Q&A pairs
- The action of carbohydrase, protease and lipase enzymes, the products of digestion, and the food tests for starch, reducing sugar, protein and fat.2Q&A pairs
- The organs of the human digestive system and their functions, the role of mechanical and chemical digestion, and the action of bile.2Q&A pairs
- The structure of the heart, the double circulatory system, and the structure and function of arteries, veins and capillaries.2Q&A pairs
Unit 1 Biology 1: Plants and ecosystems
- Food chains, food webs and trophic levels, pyramids of biomass, and the transfer and loss of energy and biomass between trophic levels.2Q&A pairs
- 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.2Q&A pairs
- 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.2Q&A pairs
- The carbon cycle and the nitrogen cycle, the role of decomposers and named bacteria, and how human activity affects these cycles and biodiversity.2Q&A pairs
- Transpiration as the loss of water vapour from a plant, the transpiration stream, and the factors affecting the rate of transpiration.2Q&A pairs
Unit 4 Biology 2: Cells, genetics and evolution
- Cell division by mitosis and meiosis, the differences between them, and stem cells and their uses.2Q&A pairs
- The classification of living things into groups, the use of keys to identify organisms, and the importance of biodiversity.2Q&A pairs
- DNA, genes and chromosomes, dominant and recessive alleles, and using genetic diagrams to predict the inheritance of a characteristic.2Q&A pairs
- Genetic and environmental variation, the theory of evolution by natural selection, and the evidence for evolution.2Q&A pairs
Unit 4 Biology 2: Microorganisms and disease
- Culturing microorganisms on agar, the use of aseptic technique to avoid contamination, and the related practical.2Q&A pairs
- The body's defences against pathogens, including physical and chemical barriers and the role of white blood cells.2Q&A pairs
- Pathogens as disease-causing microorganisms, the types of pathogen, how communicable diseases spread, and how their spread is reduced.2Q&A pairs
- How vaccination produces immunity, how antibiotics treat bacterial infections, and the problem of antibiotic resistance.2Q&A pairs
Unit 4 Biology 2: Response and regulation
- Homeostasis as keeping a constant internal environment, and how body temperature is controlled by the skin.2Q&A pairs
- Hormones as chemical messengers, the control of blood glucose by insulin, and diabetes.2Q&A pairs
- The structure of the eye and the function of its parts, how the eye focuses light (accommodation), and the pupil reflex.2Q&A pairs
- The structure of the nervous system, the pathway of a nervous impulse, and the reflex arc as a fast automatic response.2Q&A pairs
Unit 2 Chemistry 1: Rate of chemical change
- The effects of temperature, concentration, pressure, surface area and catalysts on the rate of reaction, explained by collision theory.2Q&A pairs
- Methods of measuring rate by gas volume, mass loss or a colour change, the required practical, and interpreting rate graphs.2Q&A pairs
- The rate of reaction as how fast reactants are used or products form, and collision theory in terms of frequency and energy of collisions.2Q&A pairs
Unit 2 Chemistry 1: Substances and atomic structure
- Sub-atomic particles and their relative masses and charges, working out particle numbers from atomic and mass number, isotopes, and calculating relative atomic mass.2Q&A pairs
- Word and balanced symbol equations with state symbols, the law of conservation of mass, and explaining apparent mass changes.2Q&A pairs
- How electrons fill shells, the electronic structures of the first twenty elements, and linking outer electrons to group and shells to period.3Q&A pairs
- Classifying substances as elements, compounds or mixtures, reading chemical formulae, and distinguishing physical changes from chemical reactions.2Q&A pairs
- 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 0.2Q&A pairs
Unit 2 Chemistry 1: The Earth and its resources
- The greenhouse effect and human causes of climate change, the products of combustion, and the pollutants from burning fuels and their effects.2Q&A pairs
- Thermal decomposition of limestone, the reactions of the limestone cycle, and the uses of limestone, quicklime, slaked lime and cement.2Q&A pairs
- The composition of the present-day atmosphere and how the early atmosphere changed, including the roles of oceans, plants and the early volcanic atmosphere.2Q&A pairs
- The treatment of water to make it safe to drink, the testing of water purity, and solubility including the idea of saturated solutions.2Q&A pairs
Unit 5 Chemistry 2: Acids, metals and energy
- Acids, bases and alkalis, the pH scale and indicators, and neutralisation as a reaction between an acid and a base.2Q&A pairs
- Electrolysis as the breakdown of an ionic compound using electricity, the products at the electrodes, and the extraction of aluminium.2Q&A pairs
- Exothermic and endothermic reactions, examples of each, and reaction profile diagrams showing activation energy.2Q&A pairs
- The reactions of acids with metals, bases and carbonates, the salts produced, and how to prepare a soluble salt.2Q&A pairs
- The reactivity series, displacement reactions, and how the method of extracting a metal depends on its reactivity.2Q&A pairs
Unit 5 Chemistry 2: Bonding and properties
- Covalent bonding as the sharing of electrons between non-metals, simple molecular substances, and their properties.2Q&A pairs
- Giant covalent structures such as diamond and graphite, metallic bonding, and how each structure explains the properties of the substance.2Q&A pairs
- Ionic bonding as the transfer of electrons between metals and non-metals, the formation of ions, and the properties of ionic compounds.2Q&A pairs
- Linking the type of structure and bonding to the properties of a substance, and using properties to identify the bonding type.2Q&A pairs
Unit 5 Chemistry 2: Organic and industrial chemistry
- Alkanes and alkenes, the test for an alkene, the combustion of hydrocarbons, and cracking to make smaller useful molecules.2Q&A pairs
- Crude oil as a mixture of hydrocarbons, fractional distillation, and the properties and uses of the fractions.2Q&A pairs
- Reversible reactions, the symbol used, energy changes in reversible reactions, and the idea of a dynamic equilibrium in a closed system.2Q&A pairs
- The Haber process for making ammonia, the conditions used, and why these conditions are a compromise.2Q&A pairs
Unit 3 Physics 1: Electricity and the grid
- Electric current, potential difference and resistance, the equation V = IR, and the current-voltage graphs for a resistor, a filament lamp and a diode.2Q&A pairs
- 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.2Q&A pairs
- Electromagnetic induction in a generator, how a transformer changes voltage, and the difference between step-up and step-down transformers.2Q&A pairs
- The rules for current and potential difference in series and parallel circuits, and how resistance combines in each.2Q&A pairs
- The structure of the National Grid and why electricity is transmitted at high voltage to reduce energy loss.2Q&A pairs
Unit 3 Physics 1: Energy resources and efficiency
- Renewable and non-renewable energy resources, how power stations generate electricity, and the advantages and disadvantages of different resources.2Q&A pairs
- Energy stores and transfers, the conservation of energy, wasted energy, and calculating efficiency.2Q&A pairs
- Heat transfer by conduction, convection and radiation, and methods of reducing energy loss from a house such as insulation.2Q&A pairs
Unit 3 Physics 1: Waves
- Transverse and longitudinal waves, the features of a wave (amplitude, wavelength, frequency, period), and the wave equation.2Q&A pairs
- The reflection of waves and the law of reflection, and the refraction of waves as they change speed when crossing a boundary.2Q&A pairs
- The electromagnetic spectrum in order, its common properties, and the uses and dangers of each type of electromagnetic wave.2Q&A pairs
- Total internal reflection, the critical angle, and the use of total internal reflection in optical fibres and prisms.2Q&A pairs
Unit 6 Physics 2: Forces and motion
- Speed and average speed, acceleration, and interpreting distance-time and velocity-time graphs.2Q&A pairs
- Balanced and unbalanced (resultant) forces, Newton's laws of motion, and the equation force equals mass times acceleration.2Q&A pairs
- Thinking, braking and stopping distances, the factors that affect them, and how vehicle safety features reduce injury.2Q&A pairs
- Work done, power, kinetic and gravitational potential energy, and the conservation of energy in mechanical situations.2Q&A pairs
Unit 6 Physics 2: Kinetic theory
- Gas pressure in terms of particle collisions, and how pressure changes with temperature and with volume.2Q&A pairs
- The particle model of solids, liquids and gases, density, and changes of state as physical changes.2Q&A pairs
- Specific heat capacity and the equation for energy, internal energy, and the energy needed for a change of state.2Q&A pairs
Unit 6 Physics 2: Space and radioactivity
- Half-life as the time for the activity to halve, calculating remaining activity, and uses such as dating and medicine.2Q&A pairs
- Nuclear fission and the chain reaction in a reactor, nuclear fusion in stars, and the difference between them.2Q&A pairs
- The structure of the Solar System, the role of gravity in orbits, and how a star is formed and stays stable.2Q&A pairs
- Radioactive decay, the properties of alpha, beta and gamma radiation, their penetrating power, and the dangers and uses of radiation.2Q&A pairs
Unit 7: Practical and enquiry skills
- Analysing results: plotting and interpreting graphs, drawing a conclusion, and evaluating the reliability and validity of an investigation.2Q&A pairs
- Carrying out an investigation: choosing apparatus, taking accurate and precise measurements, repeating readings, and recording results in a table.2Q&A pairs
- Planning an investigation: the independent, dependent and control variables, a hypothesis, a fair test, and risk assessment.2Q&A pairs