6.5.1 - Ecosystems

• define habitat

  the place where an organism lives (e.g -rocky shore or a field)
• define population

  all the organisms of one species in a habitat
• define a community

  all the populations of different species who like in a habitat and interact with each other
• define producer

  An organism that produces organic molecules using sunlight energy (e.g -plants)
• define consumer

  an organism that eats other organisms (animals and birds)
• define decomposer

  an organism that breaks down dead or undigested organic material (e.g- baceria or lungs).
• define trophic level

  a stage in a food chain occupied by a particular group of organisms (e.g - producers are the first trophic level in a food chain)
• what is an ecosystem?

  all the organisms living in a certain area and all, the non-living conditions factors are found here.
• • Why is an ecosystem dynamic?

  Dynamic Ecosystem refers to an ecosystem that is constantly changing and interacting with its environment and components.
• what are three types of change in an ecosystem that affect population size?

  • cyclic changes - these changes repeat themselves in a rhythm.

  • directional changes - they go in one direction and tend to last longer than the lifetime of organisms within the ecosystem.
  • unpredictable/ erratic changes - these have no rhythm and no contrast direction
• define biotic factors and abiotic factors

  • biotic - the living features of an ecosystem (e.g - presence of predators or food)
  • abiotic - the non-living features of an ecosystem (e.g - temp, rainfall, topology (shape of land) and soil nutrient availability, pH and salinity (salt content) of the water.
• what are the biotic factors in rock pools?

  seaweed can be a food source for consumers such as limpets that graze on this producer. Intense competition for food can limit the number of organisms that are present in a small rock pool ecosystem.
• what are the biotic factors in a playing field?

  producers include grass and other plants such as clover and da9ises. the large amount of these plants might attract a large number of organisms that use them as a food source ( such as rabbits + caterpillars)
• what are the biotic factors of a large tree?

  insects can use the leaves of a tree as a source of food. however if they consume all the leaves on the tree, they can slow down the tree growth and even lead to its death
• what are the abiotic factors of rock pools?

  rock pools are influenced by the tides. At high tide they are submerged by the ocean so experience abiotic fact (temp , salinity ) to the oceans ecosystem. low tide experience more extreme abiotic condition ( higher temp + salinity) - only some organisms can tolerate
• what are the abiotic factors in playing field

  rainfall and sunlight affect the growth of the producers in the ecosystem
• what are the abiotic factors in a large tree?

  drought conditions can negatively impact the growth of a tree