Ecosystems Flashcards
Definition of ecosystem?
Community of organisms along with all the non-living conditions
Definition of ecology?
is about how living things react with each other and their environment
Definition of biodiversity?
Many different species living in a particular area at a particular time
Definition of community?
All plants and animals that live in the habitat
Definition of habitat?
The place where the organisms live
Definition of niche?
The role/job of an organisms
Definition of species?
Reproduce to give fertile offspring
Definition of biotic factors?
Problems caused by other living organisms present in the community
e.g. predators, prey and competition
Definition of abiotic factors?
Problems caused by non-living organisms present in the community
e.g. temperature, rainfall, pH, minerals in the soil and drought
Definition of organism?
An animal, plant or single-celled life form
Definition of natural ecosystems?
Where humans don’t control it
e.g. woodland or oceans
Definition of artificial ecosystems?
where humans do control it
e.g. fields, greenhouse or a fish farm
Definition of interdependence?
When species depend on each other for resources
Definition of producers?
All plants
Definition of consumers?
All animals
Definition of trophic level?
Each step or stage along a food chain
Definition of top carnivore?
Not eaten by anything else (whilst it’s alive)
Definition of efficiency?
Efficiency of energy transfer means how good it is at passing on energy from one level to the next
What is the formula to calculate efficiency?
efficiency is energy available to the next level divided by energy that was available to the previous level x 100
Definition of interspecific competition?
competition between organisms from different species
Definition of intraspecific competition?
competition between organisms from the same species
Definition of mutualism/symbiosis?
a relationship between 2 organisms from which both benefit
e.g. bees and flowering plants, oxpecker and buffalo or finch and tortoise
Definition of parasitism?
The parasite takes what it needs to survive but the host doesn’t benefit
e.g. fleas
Definition of population?
All the organisms of one species living in a habitat
Definition of indicator species?
Some organism are very sensitive to change in their environment and so can be studied to see the effect of human activities - these at known as indicator species
Definition of biodiversity?
biodiversity is the variety of living organisms in an ecosystem. if the number of different species in an area decreases then the biodiversity decrease. Humans affect biodiversity usually in a negative way.
What is an example of a low biodiversity biome?
Desert
Arctic
Australian Outback
What is an example of a high biodiversity biome?
Great Barrier Reef
Jungle
Tropical Rain Forest
What is Eutrophication?
1) Nitrates are put onto fields as fertilisers
2) They dissolve into the water
3) If it rains it “runs off” the fields into streams
4) The excess nitrates cause algae to grow fast and block out light
5) Plants underneath can’t photosynthesise so die
6) Due to the dead plants micro-organisms increase and use up the oxygen
7) Organisms that need the oxygen for aerobic respiration die e.g. fish
8) Result in decrease of biodiversity but increase of indicator species
What is a pyramid of biomass?
Shows how much energy there is at each stage in the food chain
Why do animals become extinct?
Hunting No food/water Natural disasters Used for medicine/clothes/accessories Deforestation Pollution Competition
How can we help endangered species ?
Protecting habitats Legal protection Education programmes Captive breeding programmes Creating artificial ecosystems Reforestation
What is intensive farming?
Monoculture Small spaces No disease/predators/competition No extra energy wasted use of herbicides/pesticides Increased Yield Price is less Quicker and easier
Give an example of intensive farming.
Battery hens
What is organic farming?
Polyculture Takes up more land and time Produce is better Only use organic manure/compost Crop rotation Weeding No herbicides/pesticides/fungicides used Price is more Yield is less
Give an example of organic farming.
Free range hens
what is hydroponics?
When you grow crops without soil and instead use water with nutrients and minerals so that you can have fruit and veg all year round
What are the benefits of hydroponics?
Less pesticides used Environmentally friendly Great for co-existing species as it doesn't destroy their habitat Cheaper Quicker Still tastes as good
How many people do not have access to potable drinking water?
1.4billion
What are the stages of the water cycle?
1) Evaporation
2) Transpiration
3) Condensation
4) Precipitation
5) Transportation
What are the stages for water purification?
1) Filtration
2) Sedimentation
3) Chlorination
How can we collect/sample organisms?
Quadrats Pit-fall traps Longworth mammal traps Sweep nets Dip nets Pooters
When does drought occur?
When there isn’t enough precipitation.
What is desalination?
When you produce potable water from salt water. There are many methods to do this such as reverse osmosis.
What is reverse osmosis?
1) Salt water is first treated to remove solids before being fed at a very high pressure into a vessel containing a partially permeable membrane.
2) The pressure causes the water molecules to move in the opposite direction to osmosis - from a higher salt concentration to a lower salt concentration.
3) As the water is forced through the membrane the salts are left behind by removing them from the water.
What does the Carbon cycle show?
It shows how Carbon is recycled
Summarise how the Carbon cycle works?
1) Living things are made up of elements they take from the environment e.g. plants take Oxygen and Carbon from the air and Nitrogen from the soil.
2) They turn these elements into the complex compounds (carbohydrates, proteins and fats) that make up living organisms. Elements are passed along food chains when animals eat the plants and each other.
3) The elements are recycled - waste products and dead organisms are broken down by decomposers and the elements in them are returned to the soil or air, ready to be taken in by new plants and put them back into the food chain.
What does the Nitrogen cycle show?
It shows how Nitrogen is recycled
How much Nitrogen is there in the atmosphere?
78%
What are the 4 different types of bacteria involved in the Nitrogen cycle?
Decomposers
Nitrifying Bacteria
Nitrogen - Fixing Bacteria
Denitrifying Bacteria
What is the role of Decomposers?
The decomposers (bacteria and fungi) break down proteins in rotting plants and animals, and urea in animal waste and turns it into ammonia. Ammonia forms ammonium ions in solution that plants can use. This returns the nitrogen to the soil - so the nitrogen is recycled.
What are the 3 factors affecting the rate of decay?
Temperature
Water availability
Oxygen available
What are ditritivores?
Worms/maggots/woodlice they eat the dead organic matter. They increase the rate of decay by producing a large surface area.
