science review

• Energy sources


  Nuclear, Solar, Wind turbine, Fossil fuels, Hydroelectric
• Energy transfers


  1. Solar panels

  2. Wind turbines

  3. Fossil fuel power station

  4. Nuclear power station

  5. Hydroelectric energy
• Conductor


  Material that allows electric current to flow
• Insulator


  Material that does not conduct electric current and has high resistance
• Circuit symbols


  • Cell
  • Battery
  • Ammeter
  • Voltmeter
  • Lamp
  • Switch
  • Resistor
• Resistor, ammeter and battery in a circuit

  Resistor changes electron velocity, ammeter measures velocity, battery provides electrons
• Current in a series circuit

  The same at any point
• Current in a parallel circuit


  Divided when passed by another route
• Voltage in a series circuit

  Divided and changes

  
• Voltage in a parallel circuit


  Doesn't change
• Raw materials


  • Copper
  • Aluminium
  • Iron
  • Zinc
  • Limestone
  • Sand
  • Oil
  • Natural gas
• Specialised cells


  • Nerve cell
  • Muscle cell
  • Red blood cell
  • Sperm cell
  • Egg cell
  • Root hair cell
  • Guard cell
• Cell


  Basic unit of life
• Tissue


  Group of cells with similar structure and function
• Organ


  Structure made up of different tissues that performs a specific function
• Organ system


  Group of organs that work together to perform a specific function
• Organism


  Living thing
• Properties of materials can be used to predict and design clothing
• Speed


  Distance divided by time
• Organ systems


  • Respiratory
  • Circulatory
  • Digestive
  • Nervous
  • Skeletal
  • Muscular
• Respiratory system


  • Facilitates gas exchange, allows oxygen in and carbon dioxide out
  • Organs have specific roles like filtering and humidifying air
• Asthma causes inflammation and narrowing of the airways, making it difficult to breathe
• How exercise affects breathing

  Increased demand for oxygen prompts faster and deeper breathing to deliver more oxygen to muscles
• Similarities between human and fish breathing


  Both use a respiratory system to obtain oxygen and release carbon dioxide, but humans breathe air using lungs while fish extract oxygen from water through gills
• Composition of air


  Nitrogen 78%, Oxygen 21%, Carbon dioxide 0.04%, Water vapour variable
• Gas exchange in alveoli

  Oxygen diffuses into bloodstream from high to low concentration, Carbon dioxide diffuses into lungs from high to low concentration
• pH scale


  Identifies whether something is a strong acid, weak acid, neutral, weak alkali or strong alkali
• BMI


  Mass (kg) divided by height (m) squared
• Properties of metals


  • Shiny, Sonorous, Malleable
• Alloy


  Mixture of metals with improved properties
• Biodiversity


  Variety and variability of life on Earth
• Sampling techniques


  • Net
  • Pitfall trap
  • Pooter
  • Quadrant
• Riding position


  • Reduces frontal area, decreasing air resistance
• Riding formation (how the cyclists are grouped)

  • Riding in a tight formation reduces individual air resistance by drafting off the cyclist in front, effectively reducing drag for all cyclists in the group
• Properties of metals


  • Shiny
  • Sonorous
  • Malleable
• Alloy


  A material made by combining two or more metals
• Sampling techniques


  • Net
  • Pitfall trap
  • Pooter
  • Quadrant
• Quadrat sampling


  1. Measure field area

  2. Take random samples

  3. Calculate average organisms per sample

  4. Estimate total population size
• Indicator species


  • Blackspot fungus
  • Bloodworm
  • Freshwater shrimp
  • Lichen
  • Sludge worm
  • Stonefly larva
• Indicator species


  Organisms that can be used to detect various types and levels of pollution