Organising an ecosystem Flashcards
What is the order in a food chain
Producer
Primary consumers - herbivores
Secondary consumers - carnivores
Tertiary consumers
What is a producer
Organism that makes its own food usually by photosynthesis
What is a food chain
Representation of the feeding relationships within a community
What is a consumer
Organism that eats other organism for food
What is a herbivore
Organism that only eats producers (plants/algae)
What is a predator
Organism that kills and eats other organisms
What is a prey organism
Organism that is killed and eaten by another organism
What is an apex predator
Carnivore with no predators
What is the tropic levels of an organism
The number of steps it is from the start of its food chain
What does the pyramid of biomass represent
Relative amount of biomass at each tropic level of a food chain
What proportion of biomass is transferred from each tropic level to the one above
Approx 10%
Why is biomass lost between tropic levels
Respiration
Not all matter eaten is digested some is removed as waste products
Some absorbed materials is lost as waste
Energy is used in moment
Energy is used to keep animals warm
What is the carbon cycle
Process that returns carbon from organisms to the atmosphere as carbon dioxide which can then be used by plants
Explain processes that release carbon dioxide into the atmosphere
Factories burning fossil fuels
Decay and decomposition of microorganisms as they respire
Respiration in humans and animals
Explain processes that remove carbon dioxide from the atmosphere
Dissolved into water and oceans
Photosynthesis in green plants
What is the water cycle
Process that provides fresh water for plants and animals on land before draining into seas and rivers
What is condensation
As moist air rises it cools. Water vapour condenses back into liquid water droplets producing clouds
What is precipitation
As water droplets in clouds get heavier they fall as rain, snow and hail
What is evaporation
Water turning from a liquid to a gas when heated
What is a transpiration
Water movement through a plant and it’s evaporation from the leaves of stem
What is percolation in the water cycle?
Water trickling through gaps in soils and rocks
What is a decomposer
Organism that breaks down dead plant and animal matter
What are two examples of a decomposer?
Fungi
Bacteria
What is the role of decomposition
Returns carbon to the atmosphere and mineral ions to the soil from dead matter
What factors affect the rate of decay by decomposers
Oxygen levels
Moisture levels
Temperature
pH
What can compost produced from decay be used for
Fertilised for growing garden plants or crops
What type of decomposition happens when there is a lack of oxygen
Anaerobic decomposition
What gas does anaerobic decay release and how can this gas be used for
Methane
Used as a fuel
What environmental factors affect the distribution of a species in ecosystems
Temperature - warming temps lead to migration
Availability of water - during droughts animals have to move away
Composition of atmospheric gases -
Describe the methods for the decay practical
5cm cubed of milk and 7 cm cubed of sodium carbonate in test tube
Add indicator phenolphthalein which will turn pink - alkali
5 cm cubed of lipase in test tube
Place both test tubes in water bath with thermometer start at 20 degrees
Use pipette to transfer 1cm cubed of lipase into milk solution
Start timer
When solution returns white stop timer - solution is now acidic
Why does the milk solution become acidic after lipase is added in the decay practical
Lipase enzyme breaks down fat molecules into fatty acids and glycerol
Fatty acids turn solution acidic
What is the independent variable
What you change
What is the dependent variable
What you measure
What is the control variable
What is kept constant
