B7 Flashcards
what is a producer
a living thing that makes its own food from sunlight, air, and soil
producers are always
photosynthetic organisms
what are producers eaten by
primary consumers
who eat primary consumers
secondary consumers
what are prey
the animals that are eaten
what are secondary consumers eaten by
tertiary consumers
what is a stable community
one where all biotic and abiotic factors are in balance
what are predators
the animals that kill and eat prey
what are trophic levels
different stages in the food chain
what are apex predators
a predator at the top of a food chain, without natural predators
what is biomass
dry mass of a living organism
what do pyramids of biomass show
the relative biomass at each trophic level
what do the pyramids of numbers show
number of animals
approximately how much of the biomass of each trophic level is transferred to the next
10%
how is biomass lost
- not all of the biomass can be eaten
- heat is lost to the surroundings
- waste products such as co2 and urea or faeces
what is interdependence
interdependence describes how organisms ina community depend on other organisms for vital services e.g. food, shelter, reproduction
what is an abiotic factor
a non-living factor
name 7 abiotic factors that can affect a community
- light intensity
- temperature
- moisture levels
- soil ph and mineral content
- wind intensity and direction
- co2 levels
- o2 levels for aquatic animals
what is a biotic factor
a living factor
name 4 biotic factors that can affect a community
- food availability
- new predators
- new pathogens
- competition
define structural adaptation
the physical features which allow them to compete
give an example of structural adaptation
sharp teeth to tear meat apart, camouflage, thick layer of fat for insulation
define behavioural adaption
behaviours which give them an advantage
give an example of behavioural adaption
individuals playing dead to avoid predators, basking in the sun to absorb heat, courting behaviour to attract a mate
define functional adaptation
processes such as repreduction, metablosim and temperature regulation which allow them to compete
give an example of functional adaption
late implantation of embryos, conservation of water through producing little sweat
what are extremophiles
animals that live in environments which have extreme conditions e.g. high temperature, pressure and salt concentration
give an adaptation an extremophile may have in cold climates
smaller surface area to volume ratio to reduce heat loss via energy transfer, lots of insulation
give an adaptation an extremophile may have in dry climates
adaptions to kidneys sot hat they can retain its of water and produce very concentrated urine, being active in early morning and evenings when its cooler, resting in shady areas, large surface area to volume ratio to increase heat loss via energy transfer
give an adaptation an extremophile may have in plant adaptations
curled leaves to reduce water loss, extensive root systems to take in as much water as possible, waxy cuticle to stop water evaporating, water storing tissue in stem
what is te role of a produce
use energy from sunlight to make glucose during photosynthesis
what is abundance
the number of species in an area
what is distribution
the number of specie changes from one area to another
diff between a quadrat and transect
the quadrat is the square, the transect is the line [we use them for smapling]
describe the carbon cycle
Carbon is taken out of the atmosphere in the form of carbon dioxide by plants and algae during photosynthesis (the carbon is used to make glucose, which can be turned into carbohydrates, fats and proteins – biomass – within plants and algae).
This carbon is passed on to animals (and microorganisms) when they feed on plants and algae.
It is returned to the atmosphere in the form of carbon dioxide, during respiration by plants, animals and microorganisms (that release CO2 during decomposition).
If animals and plants die in conditions where decomposing microorganisms are not present, the carbon in their bodies can be converted, over millions of years and significant pressure, into fossil fuels.
When wood or fossil fuels are burned (a process is known as combustion), the carbon within them combines with oxygen and carbon dioxide is released into the atmosphere.
describe the water cycle
Energy from the Sun turns water from a Liquid to a gas.
Plants allow some water to evaporate from their Leaves. This ensures water is continuously ‘pulled’ from the soil and travels through the plant to its leaves the transpiration stream).
When water vapour cools, water turns from a gas into a liquid.
The falling of rain, snow and sleet from the sky.
how does temperature affect the rate of decomposition
chemical reactions generally faster in warmer conditions but if it is too hot the enzymes can denature and stop decomposition. low temperatures mean there is a slow rate of reaction with the enzymes
how does water affect the rate of decomposition
microorganisms grow faster in conditions with water as it is needed for respiration. water also makes food easier to digest
how does the availability of oxygen affect the rate of decomposition
most decomposers respire aerobically
when can we use decomposition
compost (fertiliser), biogas generators to produce methane gas (fuel)
required practical: effects of temperature on decay
Make a solution of milk and phenolphthalein indicator.
Add sodium carbonate which will cause the solution to become alkaline and therefore appear pink.
Place the tube in a water bath at a specific temperature.
Add the lipase enzyme and begin stopwatch.
Time how long it takes for the pink colour to disappear (i.e. when the pH has decreased).
Repeat this at different temperatures to see at which temperature the pink colour disappears the quickest, indicating the quickest decomposition.
what do environmental changes affect
the distribution of species in an ecosystem
name 3 environmental changes
temperature, water availability, atmospheric gas conditions
what is biodiversity
the variety of different species of organisms on earth or within an ecosystem
what does a high biodiversity mean
the ecosystem will be stable and species are less dependent on each other
as humans are we having a positive or negative effect on biodiversit
negative
how are we affecting biodiversity
using more land for buildings, farmings, roads = destroying habitats
pollution = kills plants andanimals
using up raw materials quicker than they are being produced
what are peat bogs
areas of land that are waterlogged and acidic – plants living in bogs do not decay fully when they die due to a lack of oxygen
how are peat bogs
source of fuel for us and are used as a habitat particular for migrating birds
what is deforestation
the cutting down of a large number of trees in the same area in order to use the land for something else
why does deforestation happen
to provide land for cattle and rice fields and to grow crops
what problems are caused by deforestation
global warming, less co2 is being taken in, number of habitats are reducing = decreasing biodiversity
define global warming
the temperature around the world is increasing
consequences of global warming
ice caps melting, rising sea levels, temperature and rainfall levels affect migration, organisms becoming extinct
programs put into place to maintain biodiversity
- Breeding programs: to stop endangered species from becoming extinct.
- Protection of rare habitats: to stop the species here from becoming extinct, if damaged they may even be regenerated to encourage populations to live here
- Reintroduction of hedgerows and field margins around land where only one type of crop is grown: maintains biodiversity as the hedgerows provide a habitat for lots of organisms (because a field of one crop would not be able to support many organisms) and field margins provide areas where will flowers and grasses can grow.
- Reduction of deforestation and carbon dioxide production: reduces the rate of global warming, slowing down the rate that habitats are destroyed
- Recycling rather than dumping waste in landfill, reduces the amount of land taken up for landfills, and slows the rate we are using up natural resources.
how do decomposers break down dead plant and animal matrer
they secrete enzymes and the matter is broken down into small soluble food molecules and they move into the microorganism via diffusion
name 6 factors affecting food security
- increasing birth rate
- changing diets in developed countries
- new pests and pathogens
- climate change
- conflicts
- cost of agriculture input
what is food security
having sufficient food to feed the population
how do farmers increase the amount of energy that is converted to the biomass in livestock
reducing the energy transfer from the animals to the environment.
e.g. raising them in small cages = less movement, kept at high temperatures so that less energy is wasted on controlling body temp, high protein foods
ethical objections on farming techniques
animals are kept in small areas = distress, increases risk of spread of infection, standard of living is low
what restrictions have been put into place for sustainable fishing
making fish nets bigger (limits of net sizes), fishing quotas are in place
what is biotechnology
the alteration and use of living organisms to produce products for human use
what can biotechnology be used for
feed the population and provide treatments, potentially, for a number of diseases
what can produce mycoprotein
fusarium
why is mycoprotein good
it is a protein-rich food source and suitable for vegetarians
describe the production of fusarium
its grown on glucose in aerobic conditions. the fungus is harvested and purified so that it can be consumed
what are the advantages of mycoprotein
reduces land use and methane contribution
what can the insulin produced from genetically modified bacteria do
treat people with diabetes
what are some advantages of genetically modifying crops
make them resistant to pests or extreme weather conditions = increase in yields, increase nutritional value means places where they lack certain vitamins are able to have them (e.g. golden rice)
