SB9- Ecosystems And Material Cycles Flashcards
What do organisms need to stay alive
Resources
What do plants need to stay alive
Space, light, water, carbon dioxide, oxygen, warmth and mineral ions
What do animals need to stay alive
Oxygen , food and water - may also need shelter
Organisms are continually interacting with eachothwr and their environments
How big can eco system be
Large - such as a rainforest or small such as a pond
How is a community formed
All the organisms that live and interact in an eco system form a community
What is a community made up of
Populations of different species - each population lives in a particular habitat within an eco system
What is interdependence
When species depend on eachother for a resource
What does a habitat for one species also include
Other organisms that affect the population and the local environment
What is abundance
A measure of how common something is in an area - such as population size
What does a quadrat enable us to do
Estimate the population size by taking samples using a quadrat
How is a quadrat used
They are randomly placed in an area - number of individuals in each quadrat is counted
How do you calculate the population size using a quadrat - equation
Population size = number of organisms in all quadrats x (total size where organism lives / total area of quadrats)
What does a food web show
The feeding relationships between the organisms in a community - we can use them to help predict what will happen if there are changes in the eco system
What’s the order in a food web?
Producer, primary consumer (herbivore) , secondary consumer (carnivore /predator) , tertiary consumer (carnivore /predator) , top predator
Does the amount of energy received from the sun on the earth vary?
Yes!! It’s affects both the physical conditions and how much life there is in each region
How much energy is captured from the sun by photosynthesis
3 x 10^20 j of energy transferred by light from the sun
What is most of the energy transferred to from the sun
Biomass (the mass of tissues) - the rest is transferred to environment by heating during processes such as respiration - this energy can’t be used so these transfers are less useful for living things
What are trophic levels
Feeding levels on a food chain
Energy flow through the biotic components of an eco system
How do energy levels change in a food chain
A primary cconsumer takes in energy stored by plant biomass - some is stored in the consumer, some energy transferred by heating and som remains in plant biomass in faeces, urine, this energy is not available to predator so predator gets a lot less energy
What does a Sankey diagram show
Shows the energy transfers in an organism
How can we calculate the efficiency of energy transfer in an organism
Energy transferred to biomas / total energy supplies to organism
X 100 if yo want it as a percentage
What’s a pyramid of biomasses
If we measure the biomass of organisms at each trophic level in an eco system - we can display them in a pyramid of biomass
The width of the bar indicates the amount of biomass at each trophic level
How can we calculate the percentage transfer of biomass between trophic levels of pyramid
Percentage biomass transfer from producers to primary consumers = 78/809 x 100
^^ example so just divide and it equals 9.6% btw
Why is there a maximum length of a food chain
The pyramid shape helps to explain why there’s a limit - the energy stored in the biomass of the top trophic level is too little to support another level
What’s the distribution of organisms
Where organisms are found in an eco system
What are abiotic factors and give me some examples
They are non living factors that affect distribution - physical and chemical factors
Eg
Temperature, rainfall and substances in the soil
What does a belt transect measure
The effect of abiotic factors on the distribution of organisms
How do you use a belt transect
Quadrats are placed along a line in a habitat, abundance of organism is measured as well as abiotic factors in each quadrat position
Abundance changes can show which abiotic factor has the greatest effect on the organism
What is an adaption
Each species of organism have certain adaptations - that mean the organism is suited to particular conditions - if abiotic factors change, distribution of an organism may also change
What happens if there is a lack of water in a community (drought)
Few organisms can survive a drought for long, most land plants can’t survive if there roots are under water for long, if climate changes resulting in flooding or drought , species may die out
How does temperature affect distribution
Eg polar bears used to cold regions, cacti adapted to hot - all have adaptations to suit a life on that temperature , a long term temperature chance will change the distribution of some organisms aand so affect the whole community
Is light very useful for plants
Light is essential for plants and algae to grow
What are pollution and give some example
Substances that cause harm to the environment are pollutants and cause pollution, many human activities release pollutants, these can poison or harm organism
What are biotic factors
Are the organism in an ecosystem that affect other living organisms
What happened In Yellowstone park
Grey wolves were reintroduced due to huge number of elk - they want predation of elk whose numbers were out of control
What’s a predator-prey cycle
In small communities , the number of a predator and its prey may be closely related, showing population changing
What happened as a result of the reintroduction of wolves in yellow stone park
Elk number rapidly increased, increased beavers - changing the landscape by dams and large pools and muddy areas
These new habitats allowed new species to live - increasing the biodiversity
What is biodiversity
The number of different species
How can lichen be used as an indicator species for sulfur dioxide pollution in the air
Lichen grows on trees and building - mutualistic relationship between a fungus and an Alga , before this species of lichen was only found in industrial areas because it’s the only lichen that can tolerate polluted air with sulfur containing gas - look how common it is in different areas to see how polluted areas are
How has the distribution of lichen changed over the past 50 years
Thee has been a large fall in sulfur dioxide so less lichen are found
Levels of other pollutants have changed for example increasing nitrogen oxide gases from the air, vehicle exhausts, has increased the range of some lichen species and decreased the range of others
Tell me about black spot fungus as an indicator species of air pollution
It’s a pathogen of roses, fungus can’t grow well where there is a lot of sulfur pollution so roses growing in cities rarely suffered from black spot infection
Tell me about water pollution indicators (eutrophication)
Some aquatic invertebrates are useful pollution indicators
Pollution of substances such as nitrates cause eutrophication encourages growth of plants so bacteria feed on dead plants and reduce oxygen concentration which kills a lot of animals - different invertebrates are adapted to different concentrations of oxygen
How is water pollution caused
By poisonous substances released by factories such as mercury or detergents
Fertilisers and sewage are other common sources of water pollution - substances such as nitrates can cause eutrophication
Can air and water pollution be measured with sensors
These give numerical data at the time of the measurement
Pollution indicator species do not give this level of detail in measurement , but are useful as a simple assessment of long term health of an ecosystem
Why can sludgeworms live in highly polluted water
BECUASE they contain haemoglobin- idk what that means but just write it in exam lol
Bloodworms have the same adaptation
What happens in most feeding relationships
A predator kills and eats its prey then moves on to find more prey
What’s parasitism
Is a different kind of feeding relationship In which one organism (the parasite) benefits by feeding off a host organism - causing harm to the host
Where can a parasite live
Lives in or on the host
It may survive for a long time and continue to provide food for the parasite if the parasite causes limited harm
How is a tapeworm adapted to living inside their hosts intestines
Hooks and suckers attach the worms head firmly to the hosts intestine wall
Segments contain male and female sex organs so fertilisation can occur
A flattened body allows absorbtion of nutrients over whole surface without need for digestive or circulatory systems
Tell me how head lice are adapted to living on hair and skin
Sharp mouth parts can pierce skin and suck blood
Sharp claws can grip on to hair and skin
Eggs are glued to hairs to prevent them falling off
What’s a mutualistic relationship
Some organism that live together both benefit from the relationship
Eg flowers depends on insects for pollination. The flower is able to produce fertilised egg cells and the insects get nectar or pollen which it uses for food
How do coral polyps form a mutualistic relationship with single felled algae
The algae can live in the water surrounding corals, but are better protected inside a polyp - the algae go in polyps and photosynthesise and share the food they make with the coral animal
