OCR GCSE Combined Science A (J250)

Master Topic B3 of OCR Gateway Combined Science A (J250): the nervous system and reflex actions, receptors and the eye, the endocrine system and hormones, control of blood glucose and diabetes, maintaining body temperature and water balance, and hormones in human reproduction. Exam tips and Mid/Stronger/Top-band model answers for the Foundation and Higher tiers. (Plant hormones, kidney anatomy and brain-region detail are separate-science only and are not covered.)

Master Topic B4 of OCR Gateway Combined Science A (J250): ecosystems and interdependence, food chains and food webs, competition and adaptation, sampling techniques, biodiversity and human impact, and the cycling of materials (carbon and water). Required-practical methods, exam tips and Mid/Stronger/Top-band model answers for the Foundation and Higher tiers.

Master Topic B5 of OCR Gateway Combined Science A (J250): sexual and asexual reproduction, DNA, genes and the genome, monohybrid inheritance, inherited disorders and family trees, variation and mutation, evolution by natural selection and its evidence, and selective breeding and genetic engineering. Worked genetic-cross examples, exam tips and Mid/Stronger/Top-band model answers for the Foundation and Higher tiers.

Master Topic B6 of OCR Gateway Combined Science A (J250): health and disease, communicable diseases and pathogens, the immune system and vaccination, developing new medicines, non-communicable diseases, feeding the human race, and monitoring and maintaining the environment. Exam tips and Mid/Stronger/Top-band model answers for the Foundation and Higher tiers. (Monoclonal antibodies are separate-science only and are not covered.)

Master Topic C1 of OCR Gateway Combined Science A (J250): states of matter and the particle model, changes of state and heating curves, inside the atom, atomic number, mass number and isotopes, the development of the atomic model, electronic structure, and relative atomic mass. Worked calculations, exam tips and Mid/Stronger/Top-band model answers for the Foundation and Higher tiers.

Master Topic C2 of OCR Gateway Combined Science A (J250): elements, compounds and mixtures, separating mixtures, chromatography and Rf values, the periodic table and group trends, ionic bonding, covalent bonding and small molecules, and giant structures and metallic bonding. Worked examples, exam tips and Mid/Stronger/Top-band model answers for the Foundation and Higher tiers. (Transition metals and nanoparticles are separate-science only and are not covered.)

Master Topic C3 of OCR Gateway Combined Science A (J250): conservation of mass and balanced equations, introducing the mole, exothermic and endothermic reactions and reaction profiles, oxidation and reduction, acids, bases and the pH scale, reactions of acids and making salts, and electrolysis. Worked calculations, exam tips and Mid/Stronger/Top-band model answers for the Foundation and Higher tiers.

Master Topic C4 of OCR Gateway Combined Science A (J250): the reactivity series of metals, displacement reactions and redox, the properties and reactivity trends of Group 1 (the alkali metals) and Group 7 (the halogens), and predicting chemical reactions from reactivity. Worked examples, exam tips and Mid/Stronger/Top-band model answers for the Foundation and Higher tiers. (Chemical tests to identify gases and ions, flame tests and instrumental methods are separate-science only and are not covered in Combined Science.)

Master Topic C5 of OCR Gateway Combined Science A (J250): rates of reaction and collision theory, the factors affecting rate, measuring and calculating rates, catalysts and enzymes, and reversible reactions and dynamic equilibrium. Worked calculations, required-practical methods, exam tips and Mid/Stronger/Top-band model answers for the Foundation and Higher tiers. (Titration calculations, percentage yield, atom economy and gas-volume calculations are separate-science only and are not covered.)

Master Topic C6 of OCR Gateway Combined Science A (J250): the extraction of metals, sustainable extraction and recycling, crude oil and hydrocarbons, fractional distillation and cracking, the evolution of the atmosphere, greenhouse gases and climate change, and atmospheric pollutants and water treatment. Worked examples, exam tips and Mid/Stronger/Top-band model answers for the Foundation and Higher tiers.

Master Topic P1 of OCR Gateway Combined Science A (J250): the particle model and the development of the atomic model, density, states of matter and changes of state, conservation of mass, internal energy and specific heat capacity, specific latent heat, and particle motion and gas pressure. Worked calculations, required-practical methods, exam tips and Mid/Stronger/Top-band model answers for the Foundation and Higher tiers. (Pressure in fluids and atmospheric pressure are separate-science only and are not covered.)

Master Topic P2 of OCR Gateway Combined Science A (J250): scalars, vectors and forces, distance, displacement, speed and velocity, acceleration and motion graphs, the equations of motion and terminal velocity, Newton’s laws of motion, momentum, weight, mass and gravity, and forces, elasticity and Hooke’s law. Worked calculations, required-practical methods, exam tips and Mid/Stronger/Top-band model answers for the Foundation and Higher tiers.

Master Topic P3 of OCR Gateway Combined Science A (J250): static electricity and charge, electric current and charge, potential difference and resistance, series and parallel circuits, I–V characteristics, electrical power and energy, magnets and magnetic fields, electromagnetism, and the motor effect and electric motors. Worked calculations, required-practical methods, exam tips and Mid/Stronger/Top-band model answers for the Foundation and Higher tiers. (The generator effect, dynamos and loudspeakers are separate-science only; mains and domestic electricity are covered in P6.)

Master Topic P4 of OCR Gateway Combined Science A (J250): transverse and longitudinal waves, the wave equation, reflection and refraction, the electromagnetic spectrum and its uses and dangers, atomic structure and isotopes, radioactive decay and nuclear equations, and half-life and the uses of radiation. Worked calculations, required-practical methods, exam tips and Mid/Stronger/Top-band model answers for the Foundation and Higher tiers. (Ultrasound, seismic waves and nuclear fission/fusion are separate-science only and are not covered.)

Master Topic P5 of OCR Gateway Combined Science A (J250): energy stores and transfers, conservation of energy and energy diagrams, work done and power, kinetic and potential energy, efficiency, and thermal energy transfer and insulation. Worked calculations, required-practical methods, exam tips and Mid/Stronger/Top-band model answers for the Foundation and Higher tiers.

Master Topic P6 of OCR Gateway Combined Science A (J250): typical speeds, reaction time and stopping distances, car safety and collisions, energy resources, generating electricity, the national grid and transformers, and mains and domestic electricity. Worked calculations, exam tips and Mid/Stronger/Top-band model answers for the Foundation and Higher tiers. (The Solar System, the life cycle of stars and red-shift are separate-science only and are not covered.)

Exam technique for OCR Gateway Combined Science A (J250): the six-paper structure and tiers, command words, required practicals across biology, chemistry and physics, mathematical skills, interpreting graphs, six-mark extended-response questions in each science, common mistakes, and a full paper walkthrough. Build the strategy to convert knowledge into marks across the Foundation and Higher tiers.