Module 3: Glossary

• Ecosystem


  A community of interacting biotic organisms and abiotic factors, and their physical environment
• Biotic factors


  • Animals
  • Plants
  • Microorganisms
• Biotic factors


  All the living organisms in a specific region or area
• Abiotic factors


  The non-living components of the environment
• Community


  An interacting group of organisms of various species in a common location
• Population


  A community of organisms where interbreeding occurs
• Habitat


  The natural home or environment of an organism
• Environment


  The surroundings or conditions that an organism lives in
• Terrestrial


  On or relating to the Earth
• Aquatic


  In or relating to water
• Species


  A group of organisms that can reproduce with one another and produce fertile offspring
• Adaptation


  The process in which an organism changes in order to adjust to changes in it's environment (e.g. selection pressures)

  • structural
  • physiological
  • behavioural
• Selection pressures


  A factor that affects (increases/decreases) the survival and reproduction of an organism within a population
• Biodiversity


  The abundance of genetic diversity within an ecosystem
• Ecology


  Study of the relationship between different organisms and their environments
• Abundance


  The number of individuals within a population
• Distribution


  The spread of the population of a species
• Keystone species


  An organism with a disproportionately large effect on the ecosystem. Helps define an entire ecosystem
• Natality


  Birth rate
• Mortality


  Death rate
• Exponential population growth


  Continuous growth in population, proportional to size of population at the time
• Population explosion


  Sudden increase in population
• Carrying capacity


  Species highest average population size
• Variation


  Differences between an organism or groups of organisms within a species