Ecosystems Flashcards
Definition of ecosystems
A biological community of interacting organisms and their physical environment
4 Trophic levels
Tertiary consumers (top predators) Secondary consumers (carnivores) Primary consumers (herbivores) Primary producers (plants)
Primary producers are
Plants that occupy the first trophic level
They make their own food from photosynthesis
E.g. Arctic lichen
Primary consumers are
Herbivores/omnivores that occupy the next level
They eat producers
E.g. Arctic hare
Secondary consumers are
Carnivores/ omnivores that occupy the next level
They eat consumers
E.g. Arctic fox
Tertiary consumers are
Top carnivores/omnivores that occupy the top level
They eat consumers
E.g. The tundra wolf
What does a food chain show
A food chain shows how energy is passed on from one organism to another
What’s the original source of energy in a food chain
Sunlight
What happens to the amount of available energy as you go up the food chain
Why does this happen
It decreases from one stage to the next as it’s used in growth, offspring production and waste materials
Why is there a smaller number of animals at the top of a food chain (tertiary consumers)
They have less energy to support them as the energy had been lost through other stages
What is nutrient cycling?
The fact that all plants and animals depend on nutrients in food, for their health and vitality, that are constantly recycled within every ecosystem
What are the three stages of the nutrient cycle
Biomass
Litter
Soil
What is the connection between biomass and litter?
Nutrients found in Biomass fall the ground when they die to create dead organic material
What is the link between litter and soil
Nutrients from the dead organic material become part of the soil as it decomposes
What is the link between soil and biomass
Plants take up the nutrients that are dissolved within the soil
