Ecosystems 3.1

• What is the definition of a species?

  A group of organisms who can interbreed to produce fertile offspring.
• What does biodiversity refer to?

  The variety of living organisms within an area.
• How is a population defined in ecology?

  The number of individuals within a species living in a particular area.
• What is a producer in an ecosystem?


  An organism that can produce its own food using light energy from the sun.
• What defines a consumer in an ecosystem?


  An organism who has to consume food to gain energy.
• What is a herbivore?

  An animal that only eats plants.
• How is a carnivore defined?

  An animal that eats meat (other animals).
• What is an omnivore?

  An animal which eats both animals and plants.
• What is the role of a predator in an ecosystem?


  An animal which hunts other animals for food.
• What is prey in ecological terms?

  An animal that is hunted by another animal.
• What does a food chain illustrate?

  The feeding relationship between individuals.
• What is an example of a food chain?

  • Grasses → Mountain Hare → Golden Eagle
• What is a food web?

  A diagram to show all of the interlinking food chains within an environment.
• Define the terms community and ecosystem

  A community is all of the living organisms living in a particular area.

  An ecosystem consists of all the organisms (the community) living in a particular habitat and the non-living components with which the organisms interact.
• What happens to the population of deer if foxes die out due to a disease?

  The population of deer might decrease, increase, or stay the same due to the interconnectedness of the food web.
• How does the death of foxes affect the golden eagle's food source?


  With fewer foxes, there is less food for the golden eagle, leading it to eat more deer.
• If the golden eagle eats more deer due to the removal of foxes, what is the likely effect on the deer population?

  The deer population might decrease due to increased predation by the golden eagle.
• What alternative effect could occur to the deer population if foxes are removed from the food web?

  The deer population might increase if the golden eagle shifts its diet to eat more mountain hares.
• What could happen to the competition for grass if the golden eagle eats more mountain hares after the foxes die out?

  There would be less competition for grass, potentially allowing the deer population to increase.
• What is a possible outcome for the deer population if both the increase in predation by the golden eagle and the decrease in competition balance out?

  The deer population might stay the same if the effects balance out.
• What are the potential impacts on the deer population when foxes are removed from the food web?

  • Deer population might decrease due to increased predation by golden eagles.
  • Deer population might increase due to reduced competition for grass.
  • Deer population might stay the same if the effects balance out.
• Describe the interactions of niches between organisms in the environment

  A niche is the role an organism plays within a community.

  A niche relates to the resource’s organisms require in the ecosystem, such as light and nutrient availability. It can also involve competition, predation and the conditions it can tolerate such as temperature.
• Describe the nature of competition between organisms

  Competition in ecosystems will occur between organisms when resources are in short supply.

  Animals are in competition for:

  • food
  • space
  • water availability
  • mates

  Plants are in competition for:

  • nutrients
  • water
  • space
  • light/sunlight
• Describe intraspecific and interspecific competition

  Intraspecific competition occurs from individuals of the same species for all of the resources they require.

  Interspecific competition occurs from individuals of different species for one or a few of the resources they require.
• Compare interspecific and intraspecific competition

  Intraspecific competition is more intense than interspecific competition because organisms are competing for more resources.