Science Inquiry Skills

• Independent Variable 


  Factor that's deliberately changed to determine how it affects the result
• Dependent Variable 


  Factor that changes due to changed made to the independent variable
• Controlled Variables 


  Factors that are deliberately kept the same for both experimental and control groups
• Hypothesis

  • testable
  • only tests 1 independent variable
  • links independent and dependent variable
  • if, then
• Risk Assessment

  • what are possible risks of the experiment?
  • how can risks be minimised or prevented?
• Data

  • quantitative - measurements (numbers)
  • qualitative - observations (words)
  • discrete - whole numbers
  • continuous - any value (decimals, fractions)
• Tables

  • always have a title consisting of the 2 variables tested (at the top of table)
  • independent variable = left column
  • dependent variable = right roumn
  • don't forget units
• Line Graph

  • continuous, quantitative data
  • if there's a trend, line of best fit must be drawn
  • if there's no trend, individual points will be joined
• Bar and Column Graphs

  • discrete, qualitative data
• Histograms

  • generally used for categorised, discrete data
• Errors

  • human error can be avoided by taking care and double checking measurements - simple mistake: misreading a measurements etc.
  • random error can be avoided by taking multiple measurements and averaging results - unpredictable, irregular mistakes: due to limitations with measuring equipment
  • systematic error can be fixed by changing procedure or equipment - continuous, predictable errors: due to poor experiment design or faulty equipment
• Animal Ethics (3 R's)

  • refine: giving animals better living conditions, reducing pain
  • reduce: reduce number of animals tested on
  • replacement: use animals with lower sentient value or no nervous systems
• Ethics

  • voluntary participation - people shouldn't be pressured to take part
  • informed consent - participants must be given all information before giving consent (procedure, risks, etc.)
  • risk of harm - potential risks must be minimised as much as possible
  • confidentiality - identity of participant remains private
• Validity

  • tests the hypothesis fairly
  • only 1 independent variable affects the results
  • can be improved by controlling all other variables
• Reliability

  • each trial will produce similar results
  • improve reliability by repeating trails
• Accuracy

  • measurements are taken correctly
  • improve by using correct measuring tools