Sampling Organisms

• What is the purpose of using quadrats and transects in an ecosystem?

  To determine the abundance and distribution of species.
• What are abiotic factors?

  Non-living factors that affect living organisms.
• How do abiotic factors affect organisms in an ecosystem?

  • They influence the number of different organisms.
  • They can vary from place to place.
• What technique do scientists use to determine the number of organisms in an area?

  Sampling.
• What are the two methods of sampling mentioned?

  • Random sampling
  • Sampling along a transect
• What is a quadrat?

  A square frame used for counting organisms.
• How is random sampling conducted using a quadrat?

  By placing the quadrat at random locations and counting organisms inside.
• How can random sampling be used to estimate total population size?

  By using the equation: Total population size = (Total area / Area sampled) × Number of organisms counted.
• Why is it important to place the quadrat multiple times during sampling?

  • To ensure valid results.
  • To accurately represent the whole area.
• What is a transect?

  A line used to study changes in species distribution across a habitat.
• How do scientists use a transect to study organisms?

  By counting organisms at intervals along the transect.
• What is the significance of using sampling along a transect?

  • To observe how species numbers change across a habitat.
  • To gather valid data on species distribution.
• How does the species composition change on a sand dune?

  It changes as you move inland from the sea.
• What is the process of conducting a transect study on a sand dune?

  1. Place a tape measure across the dune.
  2. Use a quadrat to count plants at set intervals.
  3. Repeat the process to gather valid data.
• Where can you find more questions on random sampling and transect sampling?

  You can find them in the vision workbook.