Eco Systems, Nutrient Cycles & The Environment Flashcards
What is a producer?
An organism that makes its own food
What types of organisms are primary producers?
Photosynthetic organisms like green plants and algae that trap energy from the sun
What is a primary consumer?
An organism that feeds on producers
What is a secondary consumer?
An organism that feeds on primary consumer
What is a tertiary consumer?
An organism that feeds on secondary consumers
What are herbivores?
Herbivores are animals that only eat plants
What are carnivores?
Organisms that mainly eat animals
What are decomposers?
Organisms that break down dead matter
What do food chains show?
Food chains show the feeding relationships of different organisms and the flow of energy between the organisms
What is the difference between a food web and a food chain?
Food webs show the interactions of multiple different food chains. Food chains show one path of food dependencies.
Why are biomass transfers not 100% efficient?
Energy is lost through
- Egestion (removal of faeces)
- Excretion (removal of waste products e.g. urine)
- Respiration
- The production of inedible bones and shells
What is biomass?
The dry mass of all of the living organisms in an area
Why is dry mass used for biomass?
Because the wet mass varies as the volume of water in the organism varies
What is a biomass pyramid?
A pyramid that shows the total dry mass of organisms at each trophic level
What is a pyramid of numbers?
A pyramid of numbers shows the number of organisms at each trophic level
How do you calculate the efficiency of biomass transfers?
Efficiency=(energy transferred / total energy available) x100
How does the efficiency of biomass transfers affect the number of trophic levels in a biomass pyramid?
The less efficient the transfers, the fewer trophic levels and the fewer organisms in higher trophic levels
Name 2 different types of decomposer
Bacteria
Fungi
What are nutrient cycles?
Processes by which molecules and ions are transferred between dead and living organisms
What are the two types of decomposition?
• aerobic decomposition (with oxygen).
• anaerobic decomposition (without oxygen).
How is a rising human population negatively impacting the environment?
More space is needed for housing, work and leisure which leads to the destruction of habitats which can threaten organisms that live there
What are intensive farming methods?
Ways of farming to maximise the potential yield (e.g. by using fertilisers, pesticides or battery farming).
How can fertilisers and pesticides help agriculture?
•Fertilisers provide the plant with all the nutrients it needs so that it can grow more quickly.
•Pesticides kill pests that could harm the growth of the plant.
State 2 methods of pest control
•Biological control
•Pesticides
