AQA Combined Science Paper 1 Revision Notes PDF

Let's delve even deeper into the AQA Combined Science Paper 1 topics: Biology * Cell biology: * Cell structure: Detailed look at organelles: * Nucleus: Contains DNA, controls cell activity. * Cytoplasm: Gel-like substance where reactions occur. * Ribosomes: Protein synthesis....

Let's delve even deeper into the AQA Combined Science Paper 1 topics: Biology * Cell biology: * Cell structure: Detailed look at organelles: * Nucleus: Contains DNA, controls cell activity. * Cytoplasm: Gel-like substance where reactions occur. * Ribosomes: Protein synthesis. * Mitochondria: Respiration, energy production. * Chloroplasts (plant cells): Photosynthesis. * Cell wall (plant cells): Provides support. * Cell membrane: Controls what enters and exits the cell. * Specialised cells: Nerve cells (long, transmit electrical signals), muscle cells (contract), red blood cells (carry oxygen), root hair cells (absorb water and minerals). Adaptations of these cells. * Cell division: * Mitosis: Stages (prophase, metaphase, anaphase, telophase). Role in growth, repair, and asexual reproduction. * Cell cycle: Interphase, mitosis, cytokinesis. Control of the cell cycle. * Transport in cells: * Diffusion: Movement from high to low concentration. Factors affecting diffusion rate (surface area, concentration gradient, temperature). * Osmosis: Movement of water across a semi-permeable membrane. Water potential. * Active transport: Requires energy, movement against a concentration gradient. Examples (e.g., mineral uptake by plant roots). * Organisation: * Animal tissues: * Epithelial: Covers surfaces, protection. * Connective: Supports and connects tissues (e.g., blood, bone, cartilage). * Muscle: Contracts for movement. * Nervous: Transmits electrical signals. * Organs and organ systems: * Examples: Heart (circulatory system), lungs (respiratory system), stomach and intestines (digestive system), kidneys (excretory system). * Interactions: How systems work together (e.g., circulatory and respiratory systems for oxygen transport). * Infection and response: * Communicable diseases: * Pathogens: Bacteria (e.g., Salmonella), viruses (e.g., measles), fungi (e.g., athlete's foot), protists (e.g., malaria). * Transmission: Direct contact, air, water, vectors. * Immune responses: * White blood cells: Phagocytes (engulf pathogens), lymphocytes (produce antibodies). * Antibodies: Specific proteins that bind to antigens. * Antigens: Molecules on the surface of pathogens. * Vaccinations: * Mechanism: Introduce a weakened or inactive form of the pathogen, stimulating antibody production. * Herd immunity: Protection of a population when a large percentage is immune. * Bioenergetics: * Photosynthesis: * Equation: 6CO₂ + 6H₂O → C₆H₁₂O₆ + 6O₂ * Factors: Light intensity, carbon dioxide concentration, temperature. Limiting factors. * Uses of glucose: Respiration, starch production, cellulose production. * Respiration: * Aerobic: Requires oxygen, produces lots of ATP. * Anaerobic: Does not require oxygen, produces less ATP. Lactic acid formation. * Comparison: Efficiency, products. Chemistry * Atomic structure and the periodic table: * Atomic structure: Proton number (atomic number), nucleon number (mass number). Isotopes (same number of protons, different number of neutrons). Electron configurations (e.g., 2,8,8). * The periodic table: Groups (vertical columns), periods (horizontal rows). Trends in properties (e.g., reactivity, electronegativity). Mendeleev's contributions. * Ionic compounds: Formation of ions (cations and anions). Ionic bonding (electrostatic attraction). Properties (high melting point, brittle, conduct electricity when molten). * Bonding, structure, and the properties of matter: * Covalent bonding: Sharing of electrons. Single, double, and triple bonds. Properties of simple molecular substances (low melting point, non-conductors). * Metallic bonding: Delocalised electrons. Properties of metals (high melting point, malleable, ductile, good conductors). * States of matter: Arrangement and movement of particles in solids, liquids, and gases. Melting, boiling, freezing, condensation. Energy changes during state changes. * Quantitative chemistry: * Chemical measurements: Accuracy, precision. Significant figures. Moles, Avogadro's constant. * Calculations and equations: Balancing equations. Relative atomic mass (Ar), relative formula mass (Mr). Percentage yield = (actual yield / theoretical yield) x 100. * Chemical changes: * Electrolysis: Electrolytes, electrodes (anode and cathode). Products of electrolysis (e.g., electrolysis of water, copper chloride). Half equations. * Reactions of acids: Acids (proton donors), alkalis (proton acceptors). Neutralisation (acid + alkali → salt + water). pH scale. Reactions of acids with metals (salt + hydrogen) and carbonates (salt + water + carbon dioxide). * Energy changes: * Exothermic reactions: Release energy (e.g., combustion). ΔH is negative. * Endothermic reactions: Absorb energy (e.g., thermal decomposition). ΔH is positive. * Energy level diagrams: Reactants, products, activation energy. Physics * Energy: * Energy changes and stores: Kinetic energy (1/2mv²), gravitational potential energy (mgh), elastic potential energy (1/2kx²), chemical energy, thermal energy. Energy transfers (e.g., by heating, by doing work). * Efficiency: Efficiency = (useful energy output / total energy input) x 100. * National and global energy resources: Renewable (e.g., solar, wind, hydro) and non-renewable (e.g., coal, oil, gas, nuclear). Advantages and disadvantages of each. * Electricity: * Current, potential difference, and resistance: Ohm's Law (V = IR). Series circuits (total resistance = R₁ + R₂), parallel circuits (1/total resistance = 1/R₁ + 1/R₂). * Domestic electricity: Ring main circuits, fuses, circuit breakers, earthing. * Static electricity: Charging by friction. Electric fields. Sparks. * Particle model of matter: * Changes of state: Melting, boiling, freezing, condensation, sublimation, deposition. Relationship to particle movement and spacing. * Internal energy: Total kinetic and potential energy of particles. Relationship to temperature. * Specific heat capacity: Q = mcΔT (where Q is energy transferred, m is mass, c is specific heat capacity, and ΔT is change in temperature). * Atomic structure: * Atoms and isotopes: Isotopes (same number of protons, different number of neutrons). Radioactive decay (alpha, beta, gamma). Half-life. * Nuclear radiation: Ionising radiation. Uses (e.g., medical tracers, radiotherapy). Dangers (e.g., cell damage, cancer). Nuclear fission (splitting of atoms) and fusion (joining of atoms). This expanded version provides a more comprehensive overview of the topics. Remember to consult the AQA specification for the definitive list of content. Good luck with your studies!