Ecology

• What is an ecosystem

  An ecosystem is the interaction of a community of living organisms (biotic) with the non-living (abiotic) parts of their environment.
• What might plants compete for?


  Plants in a community or habitat often compete with each other for light and space, and for water and mineral ions from the soil.
• What might animals compete with?

  Animals often compete with each other for food, mates and territory.
• What is interdependence


  it describes how organisms in a community depend on other organisms for vital services
• what does interdependence include

  it includes food,shelter and reproduction eg-birds take shelter in trees,flowers are polinated with the help of bees.
• what are abiotic factors?

  Abiotic factors are nonliving factors that can affect organisms, such as light intensity, temperature, water levels, pH, iron levels, wind, carbon dioxide levels, and oxygen levels
• What are biotic factors?

  Biotic factors are living factors that can affect organisms, such as food, predators, and pathogens
• In aboitic factors:light intensity


  -light is required for photosynthesis-the rate of photosynthesis affects the rate at which the plant grows-plants can be food sources or shelter for many organisms
• In abiotic factors:temperature


  -affects the rate of photsynthesis
• In abiotic factors:moisture levels


  -both plants and animals need water to survive
• Abiotic factors:wind intensity and direction


  -wind affects the rate of transpiration in plants-transpiration affects the temperature of the plants and the rate of photsynthesis becuse it transports water and mineral ions
• Abiotic factors :co2 levels

  -CO2 affects the rate of photosynthesis in plants-affects the distribution of organsims as some thrive in high CO2 environments
• Abiotic factors:oxygen levels for aquatic animals


  -levels in water vary greatly,unlike oxygen levels in the air

  -most fish need a high concentration to survive
• biotic factors:food availability


  -more food means organisms can breed more successfully and therefore the population can increase in numbers.
• Biotic factors:new pathogens


  -when a new pathogen arises the population has no resistence to it so they can be wiped out quickly
• Biotic factors:competition 


  -if one species is better adapted to the environment than another,then it will outcompete it until the numbers of the lesser adapted species are insufficient to breed
• What are the structual adaptations?

  -sharp teeth of a carnivore to tear meat apart-camouflage such as tan/brown colour of lionesses coat,to avoid prey from spotting her
• What is the behavioural adaptations ?

  -individuals may play dead to predators

  -basking in the sun to absorb heat

  -courting behaviour to attract a mate
• What is fuctional adaptations?

  :involved in processes such as reproduction and metabolism

  -late implantation of embryos

  -conservation of water through producing little sweat
• What is an extremophile?


  they live in the environement which have extreme conditions.E.G.-bacteria which live in a deep sea vents where the pressure is very high
• In cold climates what adaptations do they have?

  -smaller surface area to volume ratio to reduce heat loss,lots of insulation(bubber,furcoat)
• In dry climates what adaptations do they have?

  -adaptaion to the kidneys so they can retain lots of water producing very concentrated urine

  -being active in the early morning and evenings when it is cooler

  -resting in shady areas,larger surface area ratio to increase heat loss
• How do the food chains starts?

  1)they begin with a producer

  -these are always photsynthetic organisms

  -through photsynthesis they make glucose

  -glucose is used to make other biological molecules in the plants,which make up the biomass
• What do the primary consumers do in the food chain?

  2)producers are eaten by primary consumers-energy is transferred through prganims in an ecosystem when one is eaten by another
• What do secondary consumers do in the food chain?

  primary consumers are eaten by secondary consumers-the animals eaten are called the prey and the consumers that kill and eat them are predators
• What do tertiary cosumers do the food chain?

  4)secondary consumers are eaten by the tertiary cosumers
• The carbon cycle


  -CO2 is REMOVED from the air in photosynthesis by green plants and algae

  -CO2 is RETURNED to the air when plants,algae and animlas respire.Decomposers respre while they return mineral ions to the soil

  -CO2 is RETURNED to the air when wood and fossil fuels are burnt as they contain carbon from photsynthesis
• The water cycle


  -the sun's energy causes water to evaporate from sea and lakes,forming water

  -water vapour is aslo formed as a result of transpiration in plants

  -water vapour rises and then condenses to form clouds

  -water is returned to the land by precipitaion and this runs into lakes to provide water fro plants and animales

  -this then runs into seas and the cycle begins again
• What is biodiversity


  the variety of differnt species of organism on earth or within an ecosystem 
• What does a great biodiversity ensures what?

  A great biodiversity ensures the stability of ecosystems by reducing the dependence of one species on another for food, shelter and the maintenance of the physical environment.
• How do you manitain biodiversity ?

  The future of the human species on Earth relies on us maintaining a good level of biodiversity. Many human activities are reducing biodiversity and only recently have measures been taken to try to stop this reduction.
• What is peat bogs?

  -it is a material that froms when plant material has not fully decyed as there is nt enough oxygen
• What are the affects of peats bogs

  -it accumulates in bogs that are acidic and waterlogged
• How are peat bogs being destroyed?

  -they are being destroyed-as they are being drained in order to create space for farming,

  peat is used as compost or dried to use as fuel as it contain carbon (releasing CO2 into the atmosphere)

  -it is being used up quicker than it id being formed as the formation process is slow
• What is deforestation


  the cutting down of large number of trees in the same area,in order to use land for something else
• What are the problems caused by deforestation?

  1)as trees contain carbon,burning them results in more CO2 being released into the environement which contributes to global warming

  2)trees take in CO2 when they photsynthesis so less trees mean less CO2 is taken in

  3)the number of habitats are reduced,decreasing biodiveristy
• What are the causes of global warming?

  -melting ice caps

  -rising sea levels-reducing habitats as low lying areas will be flooded with salty water

  -temperature and rainfall levels
• What are the trophic levels

  they are the differnt stages of the food chains
• What is level 1


  called producers and they make their own food
• What is level 2


  called primary consumers

  -herbivores that only eat plants