B7

• What is an ecosystem?

  The relationship between all living and non-living parts of a habitat
• What are the 3 levels of organisation in an ecosystem?

  Individual organisms, populations, communities
• What is a population in an ecosystem?

  Groups of individuals of the same species
• What is a community in an ecosystem?

  Made of many populations living together
• What is competition in an ecosystem?

  Organisms competing for resources
• What do plants compete for?

  Light, water, minerals from soil and space
• What do animals compete for?

  Food, mates and territory
• What is interdependence?

  When species rely on each other for food, shelter, pollination, seed dispersal etc
• Why would removing one species from an ecosystem be bad for an ecosystem?

  Because of interdependence, it can affect the whole community
• What happens in a stable community?

  All species and environmental factors are in balance so that population size stays fairly constant.
• What is an example of a stable community?

  A rain forest or ancient oak woodland
• What is an abiotic factor?

  A non-living factor that effects the community
• What is a biotic factor?

  A living factor that effects a community
• What do abiotic factors include?

  Light intensity, temperature, moisture levels, soil pH and mineral content, wind intensity and direction, carbon dioxide levels (Plants), oxygen levels (Aquatic animals)
• What do biotic factors include?

  Availability of food, new predators arriving, new pathogens, one species out-competing another
• What are adaptations?


  Features that allow an organism to survive in the conditions that they normally live in
• What is a structural adaptation?

  A physical adaptation. Features an organism has such as fur, beaks etc
• What is a behavioural adaptation?


  Something an organism does to allow it to survive
• What are functional adaptations?

  An internal working or body process that allows an organism to survive
• What are extremophiles?


  Organisms that can live in extreme conditions such as high pressure, high salt concentration, or high temperatures
• What is an example of an extremophile?

  A tardigrade
• What method can be used to study an ecosystem?

  Transect line and a quadrat
• What are decomposers?

  Organisms that break down dead or waste material
• What type of organisms are decomposers?

  Fungi and bacteria
• What do decomposers need?

  Oxygen, moisture, a suitable temperature ans suitable pH
• How do decomposers break down the waste?

  They secrete enzymes which partly digest the waste
• What do decomposers do with the small molecules produced by their enzymes?

  They take up the small, soluble molecules by diffusion
• What can decomposers be used for?

  Compost heaps
• Why do gardeners stir their compost heaps?

  Because oxygen is needed. In anaerobic conditions, methane gas is produced
• What is the carbon cycle?

  It describes how carbon is recycled in nature

  
• Why does the carbon cycle depend on decomposers?

  To return carbon to the atmosphere as carbon dioxide through respiration
• What is the water cycle?


  Describes how fresh water circulates between organisms, rivers and the sea.

  
• What is a producer in a food chain?

  It synthesises molecules
• What is an example of a producer?


  A green plant, which produces glucose molecules by photosynthesis
• What are producers eaten by?

  Primary consumers
• What are consumers eaten by?

  Secondary consumers
• What are secondary consumers eaten by?

  Tertiary consumers
• What is each level of a food chain called?

  A trophic level
• What is a predator?


  Consumers that eat other animals
• What is prey?

  The animals that are eaten by predators