Practicals

• What is the purpose of the reaction time experiment?

  To measure how quickly one reacts to a stimulus
• What materials are needed for the reaction time experiment?

  Chair, meter ruler, table, partner
• What is the purpose of the reaction time required practical in biology?

  To measure how long it takes to react to a stimulus
• What materials are needed to perform the reaction time experiment?

  A chair, a meter ruler, a table, and a partner
• Why should you use your weaker hand for the reaction time experiment?

  To make it more challenging and get a more accurate measurement
• Where should you focus your eyes during the reaction time experiment?

  On a wall across the room, using the corner of your eye
• How should your partner hold the ruler for the reaction time experiment?

  Vertically above your thumb and forefinger, with the zero mark just above your forefinger
• How many times should you repeat the reaction time experiment?

  10 times
• Why is it important to take a short rest between each trial of the reaction time experiment?

  To avoid becoming too used to the movement of the ruler
• How can you use the reaction time experiment to compare your results?

  Compare to the rest of the class or before/after taking a stimulant
• What is the conversion used to calculate reaction time from the distance the ruler fell?

  Using a conversion table
• What is the key concept behind the term "reaction time"?

  The time it takes to react to a changing stimulus in your surroundings
• How does the term "reaction time" differ from the common misconception about it?

  A better reaction time is a shorter time, as you are reacting faster
• What are the steps to perform the reaction time experiment?

  1. Place your weaker forearm across the desk with thumb and forefinger over the edge
  2. Partner holds the ruler vertically above your thumb and forefinger
  3. Focus your eyes on a wall across the room, using the corner of your eye
  4. Partner randomly drops the ruler and you close your fingers to catch it
  5. Record the distance the ruler fell
  6. Repeat this 10 times to get an average reaction time
• How can the reaction time experiment be used to compare results?

  • Compare your results to the rest of the class
  • Compare your results before and after taking a stimulant like caffeine or sugar
• What is the purpose of the investigation?

  To estimate the population size of daisies
• What equipment is needed for the investigation?

  A quadrat and a trundle wheel
• How is the area of the field measured?

  By multiplying length and width
• How should the area be divided for sampling?

  Into a 1 meter square grid
• What is the purpose of using a random number generator?

  To choose random coordinates for the quadrat
• What percentage of the total area should be sampled?

  5 to 10%
• How many positions should be sampled according to the plan?

  30 positions
• Why is it acceptable to count a flower on the edge of the quadrat?

  If over half of it is within the quadrat
• How do you estimate the total population of daisies?

  Multiply mean by total area
• What is another method of using a quadrat mentioned in the text?

  Using a transect to observe population density
• How is the transect set up for sampling?

  By laying a tape measure along the area
• At what intervals is the sampling done along the transect?

  1 meter intervals
• What is recorded during the transect sampling?

  The number of organisms counted
• What type of graph is used to show population density changes?

  A line graph
• What is the observed trend in daisy population density?

  Increases further from the gate
• What is the likely cause of the observed trend in daisies?

  People trampling them near the gate
• What is a biotic factor?

  Due to living organisms
• What are abiotic factors?

  Not due to living things