Science Knowledge Organiser: The Zoo, Explorers, and Superheroes

The Zoo - Strand One: Plant Biology and Physical Properties

• Key Definitions

  • Diffusion: A process in which particles move from a region of a liquid or gas where they are in high concentration to a region where they are in low concentration.

  • Photosynthesis: The process in which plants use light energy, carbon dioxide, and water to make glucose.

  • Guard Cells: Specialized cells surrounding the stomata that open and close to control the exchange of gases and water loss.

  • Palisade Cells: Plant tissue containing closely packed cells located in the upper layer of a leaf.

  • Spongy Mesophyll: Plant tissue in a leaf which has loosely packed cells and air spaces between them to allow for gas exchange.

  • Chlorophyll: A green pigment found in plants which collects light energy for the process of photosynthesis.

  • Seed: A structure produced during plant reproduction that contains an embryo, a food store, and a protective coat.

  • Stomata: Small holes on the underside of leaves that allow gases to move in and out of the plant.

  • Stigma: The part of the carpel on which pollen grains land during pollination.

  • Stamen: The male reproductive structures of flowering plants.

  • Ovule: The structure in plants that contains the egg cells.

  • Sepal: Structures that protect the unopened flower bud.

  • Fertilisation: The process where a male sex cell joins with a female sex cell.

  • Density: A measure of the concentration of mass in an object or material.

  • Chemical Equation: A representation that shows the reactants and products of a chemical reaction using chemical formulas.

  • Anthers: Structures that produce male sex cells, also known as pollen grains.

  • Particles: Small pieces, such as atoms or molecules, that make up a substance.

  • Petal: Structures that may be brightly coloured to attract insects to the flower.

  • Pollination: The movement of pollen from one flower to another.

• Key Learning Concepts and Facts

  • Photosynthesis involves the use of carbon dioxide and the production of both food and oxygen.

  • Photosynthesis takes place in the chloroplasts of plant cells; these are small structures containing chlorophyll.

  • Chloroplasts appear green because they contain large amounts of chlorophyll to absorb sunlight.

  • Most animals on Earth are dependent on plants for glucose (used in respiration) and oxygen (used for breathing).

  • Plants and animals are interdependent, meaning they rely on one another for survival.

  • During plant reproduction, pollination occurs when pollen grains move from the anther of one flower to the stigma of another flower.

  • Following pollination, a pollen tube grows through the tissues of the flower until it reaches an ovule inside the ovary.

• States of Matter and Density

  • In solids, particles are very close together and tightly packed, resulting in high densities.

  • In liquids, particles are close together and although arranged randomly, they are still tightly packed, giving liquids high densities.

  • In gases, particles are very far apart, which results in gases having a very low density.

  • The formula for density is:     $density = \frac{mass}{volume}$

The Zoo - Strand Two: Ecology, Variation, and Motion

• Key Definitions

  • Food chain: A way of showing what eats what within a specific habitat.

  • Energy flow: The movement of energy between different levels in a food chain.

  • Food web: A system of many food chains linked together.

  • Aerobic Respiration: The process in which energy is released from food (glucose) when oxygen is available.

  • Anaerobic respiration: The process in which energy is released from food (glucose) when oxygen is not available.

  • Fermentation: A type of anaerobic respiration in which sugars are converted to either gases (used to make bread rise) or alcohol (used to make alcoholic drinks).

  • Kilojoules: A unit of energy. Energy is measured in joules ($J$) or kilojoules ($kJ$). One kilojoule is equal to 1000 joules ($1000\,J$).

  • Pyramid of numbers: A representation of the total number of organisms at each level in a food chain.

  • Pyramid of biomass: A representation showing the biomass at each trophic level rather than the population size.

  • Bio-magnification: The process in which small amounts of harmful chemicals accumulate to cause damage higher up a food chain.

  • Biodiversity: The range of animals and plants present in a given area.

  • Species: The basic unit of classification. Individuals of different species are unable to interbreed successfully to produce fertile offspring.

  • Extinction: Occurs when a species has completely died out.

  • Speed: The distance travelled in a fixed time period, usually measured per second.

  • Distance: A numerical description of how far apart two things are.

  • Time: A term describing the order and duration of events.

  • Distance-time graph: A graph where the distance travelled is plotted on the vertical axis against the time taken on the horizontal axis.

  • Energy resource: A useful supply or store of energy.

  • Discontinuous variation: Differences between individuals in a characteristic that can only be categorized into distinct groups.

  • Continuous variation: Variation that shows a wide range of intermediate values between two extremes and can be measured.

• Key Learning Concepts and Facts

  • During anaerobic respiration, glucose breaks down without oxygen, and the chemical reaction transfers energy from the glucose to the cell.

  • Limewater is an indicator that turns milky in the presence of carbon dioxide ($CO_2$). It is used to prove that exhaled air contains more carbon dioxide than inhaled air.

  • Respiration (the production of energy) is a distinct biological process from breathing (ventilation).

  • Variation refers to the differences between individuals within a species, caused by inherited or environmental factors.

  • Food serves as a store of energy; eating transfers this energy to the animal to keep it alive and allow for activity.

  • A gene bank is a facility where scientists store seeds and cells from as many different organisms as possible to preserve biodiversity.

  • Arrows in a food chain represent the transfer of biomass from one organism to another.

  • Example food chain: maize $→$ locust $→$ lizard $→$ snake.

  • The formula for calculating average speed is:     $average\,speed = \frac{distance}{time}$

• Key Assessment Questions

  • Formulas for aerobic and anaerobic respiration must be identified.

  • Distinction between continuous and discontinuous variation with examples.

  • Explanation for why only approximately $10\%$ of energy is passed to the next organism in a food chain and how energy is lost at each level.

  • Identification of the main causes of variation in humans.

  • The definition of biodiversity and its importance in preventing extinction.

  • Methods to prevent animal extinction.

  • Definition of biomass and the construction of a pyramid of biomass.

  • Identification of the type of respiration that produces lactic acid.

  • Meaning of arrows on a food web.

  • Definition of bioaccumulation.

  • The importance of variation between different organisms.

Adventurers and Explorers - Strand One: Mechanics and Environment

• Key Definitions

  • Simple machine: A lever or gear that reduces the force required to perform a task but increases the distance travelled.

  • Microbe: A microorganism, especially bacteria, that can cause disease or fermentation.

  • Decay: The process that occurs when organic material rots or decomposes through the action of bacteria and fungi.

  • Mummification: The process of preserving a body by embalming and wrapping it in cloth.

  • Reactivity series: A list of metals arranged in order of how vigorously they react.

  • Extraction: The process used to remove a metal from its source.

  • Ore: A rock from which a metal can be extracted.

  • Thermometer: An instrument used to measure temperature.

  • Temperature: A measure of how hot an object is.

  • Hypothermia: A condition characterized by having a lower than normal body temperature.

  • Mass: The amount of material an object is composed of, measured in kilograms ($kg$).

  • Fuel: A material that burns to transfer useful energy.

  • Spirit burner: A device designed to burn liquid fuel.

  • Melt: The change of state from a solid to a liquid.

  • Force: A push or pull measured in Newtons ($N$).

  • Friction: The force that resists movement due to contact between surfaces.

  • Weight: The force of the Earth acting on an object due to its mass.

  • Energy: A quantity that determines whether a process can happen; required for work to be done.

  • Joule: The unit of energy ($J$).

  • Calories: A measure of the energy contained in food.

  • Speed: The rate at which an object moves, measured in meters per second ($\text{m/s}$).

  • Insulator: A material that does not conduct heat well.

  • Flammable: A property of a material that allows it to be burnt.

  • Mean: The average of a set of data, calculated by adding all values and dividing by the total number of values.

  • Filtration: A method for separating solid pieces mixed with a liquid or solution.

• Essential Equations

  • Speed Calculation:     $speed = \frac{distance}{time}$     where distance is in meters ($m$) and time is in seconds ($s$).

  • Weight Calculation:     $weight = mass \times gravity$     where mass is in kilograms ($kg$), weight is in Newtons ($N$), and gravity is in Newtons per kilogram ($N/kg$).

Adventurers and Explorers - Strand Two: Earth and Space

• Geological and Biological Definitions

  • Sedimentary: Rock formed from accumulated sediments.

  • Igneous: Rock formed when liquid rock (magma or lava) cools and freezes.

  • Metamorphic: Rock formed by the action of extreme heat and/or pressure.

  • Evolution: The development of a species over a long period of time.

  • Adaptation: Characteristics that help an organism survive in its specific environment.

  • Corrosion: The process by which metal, stone, or other materials are damaged by their environment.

  • Rusting: A specific chemical reaction where iron oxide is formed when iron reacts with water and oxygen.

• Astronomical Definitions

  • Season: Changes in temperature during the year caused by the Earth's movement around its orbit.

  • Day: The time taken for a planet to make one full spin on its axis.

  • Year: The length of time required for a planet to orbit a star.

  • Heliocentric: A model of the Solar System with the Sun at the center.

  • Geocentric: A model of the Solar System with the Earth at the center.

  • Solar system: The Sun, the planets, and other bodies in orbit around it.

  • Galaxy: A collection of stars and their surrounding solar systems grouped together.

  • Star: A body in space that emits its own light.

  • Universe: Everything that exists.

  • Comet: Dust particles frozen in ice that orbit the Sun.

  • Meteorite: A stony or metallic object from outer space that has fallen to Earth.

  • Satellite: An object (natural or artificial) that orbits a planet.

  • Telescope: A device used to observe distant objects in space.

  • Gravity: A non-contact field that acts between all objects that possess mass.

  • Atmosphere: The mixture of gases surrounding a planet or moon.

• Physical Properties and Safety

  • Pressure: The force exerted on a specific area.

  • Incompressible: A property of a substance that cannot be compressed or squashed.

  • Risk assessment: A description of how to make an activity less likely to cause injury or damage, including procedures for when accidents occur.

• Essential Equations

  • Pressure Calculation:     $pressure = \frac{force}{area}$     where force is in Newtons ($N$), area is in square meters ($m^2$), and pressure is in Newtons per square meter ($N/m^2$) or Pascals ($Pa$).

Science of Super Heroes - Strand One: Making Movies

• Key Definitions

  • Diffuse scattering: Reflection occurring from a rough surface.

  • Driving force: The force that is actively pushing or pulling an object.

  • Earth's Axis: The imaginary line around which the Earth spins.

  • Elastic limit: The point beyond which a spring will not return to its original length after the force is removed.

  • Electric charge: A property of a material or particle that can be positive or negative.

  • Electric field: A region where a charged material or particle experiences a force.

  • Extension: The amount an object lengthens when a force is applied.

  • Gear: A rotating lever used to reduce the force required to do work.

  • Image: A picture formed in a mirror, on a screen, or created by lenses.

  • Lever: A simple machine used to increase the size of a force or the distance a force moves.

  • Ligament: Biological tissue that joins two bones together.

  • Parallel circuit: A circuit containing two or more paths or branches for current to flow through.

  • Potential difference: The measure of the push of a cell/battery or the energy it can supply.

  • Resistive force: A force that acts to slow down a moving object.

  • Series circuit: A circuit where all components are joined in a single loop.

  • Specular reflection: Reflection occurring from a smooth surface.

  • Stretch: An action that occurs when a force is applied to an object.

  • Tension: A stretching force.

  • Voltage: The measure of the strength of a cell or battery used to send current around a circuit.

  • Work: A method of transferring energy that does not involve heating.

• Formulas and Relations

  • Hooke's Law:     $F = k \times x$     Where $F$ is force, $k$ is the spring constant, and $x$ is extension.

  • Ohm's Law / Resistance:     $V = I \times R$     Where $V$ is voltage, $I$ is current, and $R$ is resistance.

Science of Super Heroes - Strand Two: Super Abilities

• Key Definitions

  • Alkali metal: Metals in the first group (Group 1) of the periodic table; they are highly reactive and form metal hydroxides when they react with water.

  • Atmospheric pressure: The pressure exerted by the Earth's atmosphere at any given point.

  • Conduction: The method by which energy travels through a solid material.

  • Convection: The transfer of energy via the movement of liquids or gases.

  • Density: The mass of a material contained within a certain volume.

  • DNA: A chemical containing all the information required to build and maintain an organism.

  • Gas pressure: The force exerted by gas particles per unit area of a surface.

  • Gene: A section of DNA containing the information for a specific characteristic.

  • Genetic: Anything linked to genes or heredity.

  • Halogen: The name for elements located in Group 7 of the periodic table.

  • Heredity: The passing of characteristics genetically from one generation to the next.

  • Liquid pressure: Pressure produced by the collisions of particles within a liquid.

  • Noble gas: The name for elements located in Group 0 of the periodic table.

  • Unreactive: A substance that reacts with very few other substances, reacts very slowly, or does not react at all.

• Formula

  • Weight and Mass Relationship:     $weight = mass \times gravitational\,field\,strength$