9) Ecosystems Flashcards
What is an ecosystem made up of?
Abiotic and biotic parts
What are the levels of ecosystem organisation? (3)
Individuals
Populations
Communities
What are communities made up of?
Populations from different species
What are populations made up of?
Individual organisms to make up a single species
What do plants compete for? (4)
Water
Mineral ions
Light
Space
What do animals compete for? (3)
Food
Mates
Territory
What is interdependence?
One species relying on another species for different things
What do species rely on other species for? (4)
Shelter
Seed dispersal
Food
Pollination
When is a community stable?
When all the species and environmental factors are balanced and population sizes are more or less constant
What are the levels of the food chain? (5)
1) Producer makes its own food through photosynthesis (algae, plants)
2) Primary consumers
3) Secondary con sumers
4) Tertiary consumers
5) Apex predators
What do food chains show?
The feeding relationships within a community
What components are food chains made up of? (4)
Predators
Prey
Apex predators
Decomposers
What are decomposers?
The final stop for food chains, they break down dead material by secreting enzymes
Enzymes partially digest waste products and produce small food molecules
What are apex predators?
Predators which are not prayed upon
What are prey?
Animals predators eat
What are predators?
Consumers that eat other animals
What does a trophic level describe?
Where an organism fits into a food chain
What is at level 1 of the food chain?
Producers that use light energy to synthesise their own food
What is at level 2 of the food chain?
Primary consumers that eat plants/ algae (herbivores)
What is at level 3 of the food chain?
Secondary consumers that eat herbivores (carnivores)
What is at level 4 of the food chain?
Tertiary consumers that eat other carnivores
What do predator-prey graphs show?
The cyclical nature of predator and prey populations in stable communities
What is the process of a predator-prey graph?
1) An increase in prey numbers means more food is available for predators so predator numbers increase
2) The increase in predator numbers means the prey have more predators so the prey numbers decrease
3) The predators then have less food available so their numbers decrease
4) The decreasing predator numbers allows the prey numbers to increase again, and the cycle repeats
What is parasitism?
One organism benefits from the relationship but the other is harmed
What is mutualism?
Both species benefit in this relationship
What are the types of relationship between species? (4)
Predator-prey
Producer-herbivore
Mutualism
Parasitism
Why is the recycling of materials essential for future organisms?
They provide the building blocks
What does the water cycle describe?
How water moves on, or above or below the surface of our planet between different locations
What is the carbon cycle?
1) Carbon is removed from the atmosphere by producers who use it in photosynthesis
2) Animals obtain carbon compounds by consuming plant matter
3) Carbon is returned into the atmosphere because of respiration in plant and animal cells
4) When animals and plants die, decomposers return the carbon locked in their bodies back to the atmosphere via decay
5) Combustion of fossil fuels is another source of carbon entry into the atmosphere
What is the nitrogen cycle?
Nitrogen is present in all living organisms
It moves through food chains and is recycled when organisms die
What is the process of the nitrogen cycle?
1) Plants absorb nitrates from the soil and grow with the help of bacteria in roots (root nodule bacteria)
2) Plants absorb nitrogen from the air
3) Farmers may add fertilisers with root nodule bacteria to add nitrates to infertile soil
4) Nitrogen passed onto animals that eat the plants
5) Plants and animals die and bacteria recycle nitrogen back into soil through decomposition
6) Lightning strikes soil and nitrogen is released back into the air
What type of bacteria helps plants absorb nitrogen in the soil?
Root nodule bacteria
What is the process of the water cycle?
1) Water evaporates from the Earth’s surface and rises to the atmosphere
2) Water vapour in atmosphere cools and condenses to rain or snow
3) Rain or snow will become surface run off or ground water
4) Plants take up water through their roots
5) We get drinking water by filtering or adding chemicals to fresh water or by desaltinating seawater
What is responsible for recycling organic matter within an ecosystem?
Decomposers
What do decomposers produce?
Compost
How do decomposers break down dead materials?
Secreted enzymes partly digest waste products by producing small and soluble food molecules which can diffuse into the decomposer
What factors affect the rate of decay? (3)
Temperature
Oxygen availability
Moisture availability
What are the types of decomposers? (2)
Fungi
Bacteria
What methods are used to preserve food by decreasing the rate of decay? (5)
Freezing Storing in another gas Storing in oil Irradiating Salting