ECOLOGY #2 Flashcards
What do food chains always start with
they always start with a producer
what are producers and give examples
producers make their own food using energy from the sun
examples are green plants or algae
what is biomass
the mass of a living material
what are producers eaten by
primary consumers
what are primary consumers eaten by
secondary consumers
what are secondary consumers eaten by
tertiary consumers
what is the food chain
Producers———primary—-secondary——-tertiary
examples of primary consumers
herbivores - sheep fish etc
examples of secondary consumers
carnivores - lions seals etc
what happens if the population of prey increases
the population of predators increases
what happens if the population of predators increases
the population of prey decreases
what are the environmental changes that can affect the distribution of living organisms
availability of water
temperature
atmospheric gases
the water cycle
- energy from the sun makes water evaporate from the land and sea turning it to water vapour. Water is also evaporated from the plants
- the warm water vapour is carried upwards when it gets higher up it cools and condenses to form clouds
- water falls from the clouds as precipitation onto land where It provides fresh water for plants and animals
- it then drains into the sea where the process starts again
how does the water cycle benefit plants and animals
by providing them with fresh water
examples of decomposers
bacteria and fungi
what causes materials to decay
microorganisms break them down
the carbon cycle
- photosynthesis removes carbon dioxide from the atmosphere which can be used to make organic molecules.
- green plants and algae respire which returns the carbon dioxide back into the atmosphere
- animals eat the green plants and build carbon in their bodies
- when the animals respire some carbon is returned back into the atmosphere
- when plants algae and animals die organisms feed on their remains and carbon dioxide is returned into the atmosphere
- in addition to this aniamals also produce waste which is broken down by microorganisms
- the combustion of wood and fossil fuels also releases co2 back into the air
what is compost
decomposed organic matter
what is the rate of decay affected by
temp
oxygen availability
water availability
number of decay organisms
how does temp affect decay
temp- warmer temperatures make things decompose quicker because they increase the rate at which the enzymes work at
if its too hot the enzymes will be destroyed and the rate of decomposition will slow down
when its cold the rate of decomposition slows down too
how does oxygen availability affect rate of decay
many organisms need oxygen to respire which they need to do to survive
how does water availability affect rate of decay
decay happens faster in moist environments because the organisms involved in decay need water to carry out biological processes
how does the number of decay organisms affect rate of decay
the more microorganism or detritus feeders there are the faster the rate of decomposition
what are detritus feeders
Detritus feeders include things like earth worms and woodlice which help break up decaying material
what is biogas
made up of methane which can be burned as a fuel
how is biogas made
by the anaerobic decay of waste material
when plant and animal waste decay anaerobically what do they produce
methane gas
why do biogas generators need to be kept at constant temperatures
so that microorganisms can continue to respire
what are the two types of biogas generators
batch generators and continuous generators
what is a batch generator
make biogas in small batches and theyre manually loaded up with waste which is left to digest
what is a continuous generator and where are they more suited
makes biogas all the time and waste is continuously fed it and biogas is produced at a steady rate
they are more suited to a large scale biogas projects
why are green plants referred as producers
they photosynthesise and produce glucose
name three gases recycled in nature
carbon dioxide
water vapour
oxygen
what is a primary consumer also known as
herbivore
how is carbon dioxide returned to the environment from plants
respiration by cells releases carbon dioxide which diffuses from the leaves into the air by stomata
explain why the number of predators will eventually fall and the effect it will have on its prey
- predators would reduce the amount of prey animals by eating them
- fewer prey animals would mean less food for the predators making predator numbers fall
- this makes the prey number increase again
what is biodiversity
biodiversity is the variety of different species of organisms on earth or within an ecosystem
why is high biodiversity important
it makes sure that ecosystems are stable because different species depend on each other for things like shelter and food
what human actions reduce biodiversity
waste production, deforestation and global warming
what gases in the atmosphere trap energy from the sun
carbon dioxide and methane gas
consequences to global warming also explain why each problem is bad
higher temperatures cause sea water to expand and ice to melt causing sea level to rise this can cause flooding and loss of habitats in low lying area
biodiversity can reduce if some species are unable to survive a change in the climate so become extinct
how do the gases in the atmosphere increase the temp of the planet
the gases in the atmosphere naturally act as an insulating layer
the absorb most of the energy that would normally be radiated out into space and reradiate it in all directions
what do humans pollute
waterways with sewage and toxic chemicals
air with smoke and gases
land with toxic chemicals such as pesticides and herbicides
what is deforestation
deforestation is the cutting down of forests
why is deforestation done
to clear land for farming to provide more food
to grow crops from which biofuels based on ethanol can be produced
what problems may deforestation cause
less carbon dioxide taken in
more carbon dioxide in the atmosphere
less biodiversity
why does deforestation cause less carbon dioxide to be taken in
cutting down loads of trees means that the amount of carbon dioxide removed from the atmosphere during photosynthesis is reduced
why does deforestation result in more carbon dioxide in the atmosphere
if land is cleared by burning the trees this means that carbon dioxide is released into the atmosphere. Microorganisms feeding on leftover dead wood release carbon dioxide as a waste product of respiration
why does deforestation cause less biodiversity
habitats like forests contain a huge number of species of plants and animals so when trees are destroyed many species are in danger of extinction causing less biodiversity
what does more co2 in the atmosphere result in
global warming
what other than deforestation can lead to an increase in carbon dioxide in the atmosphere
the destruction of peat bogs
how do peat bogs cause an increase in co2
peat is removed from the bogs and used in compost in gardens where it is decayed by organisms releasing carbon dioxide
what has been set up to protect ecosystems and biodiversity
breeding programmes have been set up to help prevent endangered species becoming extinct
programmes to proect and regenerate rare habitats protecting these habitats helps to prtect the species that live there preserving the ecosystem and biodiversity in the area
some programmes to reduce level of deforestation which could reduce the amount of global warming
what are the conflicting pressures of maintaining biodiversity
it costs money
lose jobs- tree felling industry
food security
what are trophic levels
different stages of a food chain
whats in trophic level 1
level 2
level 3 and
level 4
level 1 contains producers
lv2- primary consumers(herbivors)
lv3 - secondary consumers (CARNIVORES)
lv4 - tertiary consumers carnivores that eat other carnivore they are top of the food chain
HOW DO DECOMPOSERS BREAK DOWN DEAD MATERIAL
THEY SECRETE ENZYMES THAT BREAK THE MATERIAL DOWN INTO SMALL SOLUBLE MOLECULES WHICH THESE ARE THEN DIFFUSED INTO THE MICROORGANISMS
why are pyramids of biomass constructed
to represent the relative amount of biomass at each level of a food chain
what trophic level is always ay the bottom
1
what is lost between ech trophic level
biomass
why is biomass lost between each tropic level
oeganisms don’t eat every single part of the organism theyre consuming
some biomass is converted into other substances that are lost as waste eg organisms use glucose to provide energy for movement instead of more biomass
effiecinecy =
biomass transferred to the next level
DIVIDED BY
biomass available at the previous level
ALL TIMES BY 100
what factors affect food security
population keeps increasing
diets in developed countries change demands for certain foods increase meaning already scare food can become more scarce
high input costs of farming
how can fish stocks be maintained
fishing quotas- limits on the number and size of fish that can be caught in an certain area this prevent certain species from being overfished
net size- this is to reduce the number of unwanted fish the one that are accidentally caubht
how can food production (from livestock) be more efficient
by limiting the movement of livestock and keeping them in a temperature controlled environment. this means that they use less energy moving around and controlling thoer own body temp so more enrgy is availabele for groeht
some aniamls can be fed high protein foods
what is mycoprotein used for
used to make high protein meat substitutes for vegetarian meals
what does biotechnology enable us to do
use large amounts of microorganisms and grow them industrially under controlled conditions in large vats for use as a food source
how is mycoprotein made
made from the fungus fusarium which is grown in aerobic conditions on glucose syrup it is then harvested and purified
how can biotechnology help
in developing countries gm crops can be produced that are resistant too pests improving crop yield]
crops can become gm to grow better in drought conditions
some crops can be modified to provide more nutritional value
disagreements with biotech
some people argue that people cannot afford the food not tht there isn’t enough
some countries might become dependent on comapainies who sell gm seeds
poor soil is the reason why some crops fail so gm crops might not even survive
