Chapter 23

• biotic factors

  • Light availability
  • temperature
  • water availability
  • oxygen availability
  • edaphic factors
• What are the 3 soil types

  1. Clay- easily waterlogged and forms clumps when wet
  2. loam- different sized particles retains water and does not become waterlogged
  3. sandy- do not retain water and are easily eroded
• What is a decomposer


  An organism that feeds on and breaks down dead plant or animal matter into inorganic nutrients for photosynthetic producers
• Why are decomposers saprotrophs


  Because they obtain their energy from dead or waste organic material
• What are detritivores


  They are organisms that speed up the decay process by feeding on dead and decaying material and break it down into smaller pieces. this increases SA for the decomposers to work on
• Prezygotic reproductive barriers


  Prevent fertilisation and formation of the zygote
• Postzygotic reproductive barriers


  Reduce the viability or reproductive potential of offspring