Ecosystems and Material Cycles Flashcards
Individual definition
A single organism
Population definition
All organisms of one species in a habitat
Community definition
All organisms of different species living in a habitat
Ecosystem definition
A community of organisms along with all the non-living abiotic conditions
What is mutualism?
A relationship where two organisms benefit from each other
What is an example of a mutualistic relationship?
Bee and flowers
- bees help the flowers reproduce
- bees receive pollen
What are parasites?
They live closely with a host species. They live either in them or on them. But the host does not benefit
What are abiotic factors?
Non-living factors that affect the community
What are biotic factors?
Living factors that affect the community
What are some abiotic factors?
- Temperature
- amount of water
- light intensity
- levels of pollutants
What are some biotic factors?
- Conditions
- Predation
How do you use a quadrat?
- throw randomly
- count organisms your interest in
- repeat a few times
- work out the mean
- compare results
What is the formula for efficiency of energy transfer?
(energy transferred to next level / energy available from previous) x 100
How can rain cause eutrophication?
- nitrates are used as fertilisers
- when it rains the nitrates can find they way into the rivers and lakes
- nitrate causes algae to grow fast and block light
- plants cant photosynthesis due to lack of light
- plants die
- microorganisms that feed off decomposing plants and take up oxygen
- causes the death of animals in the sea as they need oxygen for aerobic respiration
What is a non-indigenous species?
A species that doesn’t naturally occur in an area
What are the ways to conserve biodiversity?
- reforestation
- conservation species’ natural habitat
- protecting zoos
What are the benefits of reforestation?
- brings higher biodiversity
- brings food and shelter
- brings a variety of trees and plants
What are the biological factors that affect the level of food security?
- Increasing consumption of meat and fish, and animal farming
- environmental changes caused by human activity - green house gases
- sustainability
- new pests and pathogens
What is desalination?
Removes salts (mineral ions) from salt water
What is the modern method of desilation?
- reverse osmosis
- movement of water from an area of lower salt concentration to an area of higher salt concentration
What are the indicators of low water pollution?
- stonefly larvae
- freshwater shrimps
- they are very sensitive to the concentration of dissolved oxygen in water
What are the indicators of high water pollution
- bloodworms
- sludge worms
- indicate high levels of water pollution
How can air pollution be monitored?
Looking for types of lichen that are very sensitive to the concentration of sulphur dioxide in the atmosphere
What do blackspot fungus indicate?
- found on rose leaves
- it is sensitive to the level of sulphur dioxide in the air
- shows there is clean air
Why do things decompose?
Because of microorganisms
What are the three factors that affect the rate of decay?
- temperature
- water content
- oxygen availability
What does storing food in the fridge do?
- It lowers the temp of the food
- slows the decomposers rate of reproducers
What does storing food in an airtight can do?
- stops microorganisms getting in
- they are sealed and sterilised
- they are exposed to high pressure and temp to kill the organisms
What does removing the water content in the food do?
- microorganisms wont survive and reproduce
- lose of water due to osmosis
