4.7.2.1 Levels of Organisation

Question 1

What are photosynthetic organisms?

Answer 1

photosynthetic organisms are the producers of biomass for life on Earth

Question 2

What do food chains represent?

Answer 2

feeding relationships within a community can be represented by food chains

Question 3

What is a food chain?

Answer 3

• all food chains begin with a producer which synthesises molecules
  
  • always photosynthesis organisms
  • usually a green plant or algae which makes glucose by photosynthesis
  • glucose is used to make other biological molecules in the plant, which makes up the biomass
• producers are eaten by primary consumers - energy is transferred through organisms in an ecosystem when one is eaten by another
• primary consumers are eaten by secondary consumers - the animals eaten are called the prey and the consumers that kill and eat them are oredators
• secondary consumers are eaten by tertiary consumers

Question 4

What will a stable community show?

Answer 4

• a stable community will show population cycles between the predators and prey
• if the population of prey increases, the population of predators will also increase
• this will result in the number of prey decreasing after some time as more would be consumed by the increased number of predators
• when there isn’t enough prey to feed all the predators, the population of predators will decrease, which will allow the population of prey to increase again