BIOLOGY TOPIC 7 - ECOLOGY

• community


  populations of different species living in one area
• where does competition for resources come from in animals and plants?

  animals-food,mates,territory

  plants-water,mineral ions,light,space
• for what reasons might a species rely on another species?

  shelter

  seed dispersal

  pollination

  food
• what are the requirements for a stable community?

  when all species and environmental factors are balanced and population sizes are more or less constant
• order of members in a food chain

  producer

  primary consumer

  secondary consumer

  tertiary consumer

  apex predator
• environmental impacts of temperature change

  ice caps melting, so polar bears are no longer able to hunt their main food source (seals)
• environmental impacts of changing atmospheric gases

  carbon dioxide dissolves in water and increases water acidity

  increased carbon dioxide in the atmosphere prevents the growth of coral
• causes of environmental changes

  seasons

  geological activity

  humans
• what are quadrats used for?


  estimating population size
• what are transects used for?

  investigating the effect of a factor on distribution of a species
• the water cycle (steps)

  water evaporates from earth's surface

  water vapour condenses and cools into rain or snow

  rain/snow will either become surface runoff or travel through earth as groundwater

  plants take up water through their roots
• what 2 cycles are important for living organisms?

  water cycle

  carbon cycle
• factors needed for decay

  high oxygen availability

  moisture availability

  high temperature
• method for decay practical

  use a water bath to heat all components to desired temperature

  mix milk, sodium carbonate and phenolphthalein indicator (solution should be pink)

  add lipase to solution and start timing

  when milk solution turns milky-white stop timing

  repeat using milk of different temperatures
• biodiversity definition


  variety of species in a given area
• how does industrial waste impact land?

  toxic herbicides and pesticides used in farming are pollutants
• how does industrial waste impact water?

  sewage and toxic chemicals find their way into earth's water sources
• how does industrial waste impact air?

  smoke and gases are added to the atmosphere, mainly by power stations, factories and cars
• what is peat?


  partially decomposed plant material that cover 3% of earth and store 1/3 of the world's carbon
• reasons for peat bog destruction

  free up land for farming

  burn peat for fuel

  sell peat as compost
• negative consequences of deforestation

  methane produced by cattle

  loss of biodiversity

  carbon dioxide released into atmosphere
• how is carbon dioxide removed from the atmosphere?

  photosynthesis by plants and algae
• how is carbon dioxide released into the atmosphere?

  waste product of respiration

  burning of fossil fuels
• consequences of global warming

  extreme weather events

  rising sea temperatures

  ocean acidification

  distribution of species

  reduced biodiversity

  altered migration patterns

  melting ice caps
• incentivising farmers


  farmers being paid to maintain field margins and hedgerows
• how do decomposers break down dead material?

  producing enzymes

  these enzymes digest waste products, producing soluble molecules

  these molecules diffuse into decomposer
• name 2 types of decomposer

  bacteria

  fungi
• what does a pyramid of biomass represent?

  relative amount of biomass at each trophic level in a food chain
• what is biomass?


  total mass of living material in an organism multiplied by number of organisms
• what is the general rule for transfer efficiency?

  10% of energy from a given trophic level will be available to the next trophic level
• reasons for inefficient biomass transfer

  body temperature

  movement

  excretion

  digestion
• factors impacting food security

  diet shifts in developed countries

  conflicts

  cost of agricultural input

  extreme weather events

  pests and pathogens

  increasing birth rates
• biotechnology definition


  use of biological processes to develop/make products
• how is mycoprotein produced?

  growing fungusFusariumin fermenters under aerobic conditions and using glucose syrup as a food sourcebiomass is harvested and purified to make meat substitutes
• farming techniques for increased food production

  high protein foods to help increase growth rate

  shortening food chains to increase efficiency

  limiting energy wasted by livestock
• consequences of declining fish stock

  food chains affected

  food security threatened

  fish populations at risk

  financial struggle for fishermen
• ways to fish sustainably

  controlling size of nets so smaller fish can slip out

  fishing quotas (restricting number/size of fish that can be caught legally)