Module 6.5 Flashcards
What is the importance of nitoirgen in the environment ?
how do plants and animals ge it in this way and why ?
78% nitorgen gas however , need cycle because plants and animals CANNOT OBTIN nitrognen through gas exchnage , this is becaue N2 has a triple bond .
What is needed to convert nitorgen gas into nitorgen containing substances ?
Micorganisms , so that plants can absorb it b active transport and animals can absorb b eating and digesting plants .
What is the importance of nitogen in animals
poreins , atp and nucleic acids .
nitrogen cycle can be split into four different stages ,what are they ?
1.ammonification
2.nitrification
3.nitrogen fixation
4.denitrification .
part one
START IN NITROGEN IN ATMOSPHERE .
-Nitrogen-fixing (converting n2 ) into ntirogen cntaining compounds .n
-This can be done directl in plants , in legumes , root nodules .
why can this be done directly in root nodules ?
as root nodueles have bacteira , this bacteira is able to convert inot n2 , gas into ammonium / nitrates , this is the direct route .
HOWEVER , not all plants have root nodues ,s o hwo do they do it >
root nodules can only be found in leguminous pnts - these can direcntl convert into n2 compounds in plants due to SYMBIOTIIC RELTIONSHIP (both plant and bacteria are gaining benefits ) .
check star 2
alternative if it is not a leguminous plant ( alone ) bean plants .
-There is nitrogen fixining bacteira that occurs in the soil .
-These bactria convert N2 into ammonium known as AMMONIFICATION (as we create ammonia )
star three
that ammonia needs to be nitrfied and go thru the process of nitrification before it can be absorbedby the plant . THIS HPPENS INT WO WAYS .
star four way one
nitrifying bacteria , happen 2 stages
ammonium nh4+ –> nitriles (no2-)
STAR FIVE way two
e nirifying bacteria in the soil which are able to convert to nitriles into nitrates
STAR FOUR AND STAR FIVE ARE NITRFICIATIONS TEPS .
star 6 nitrates (NO3-)
could be dissovled within the water , within the soil are able ot be abdorbed into the plant b active tranpsort .
-and they can be asimialted inot hte cell and they would be used to creare amino acids , ATP and DNA .
star 7
once in the plants , animals (eat the plants ) and nitrates get into the animals .
star 8
animals will produce , waste that constnt ammonia they will also eventully die as will the plants .
-when animals and plants die –> porteins and dna within themsleves all contain n2
-Digest porteins into other nitrogen containing compounds .
star nine
also ammonification as waste are able to be converted into ammonia and portein cucles round and round
star ten
also denitifying bcteira are bale to converte nitaes (no3-0 By DENITIFYING BACTERI .
what is an ecosytem
a community of animals , plants and bcteira inerrleated witht he phsycial and chemical neviornemnt.
abiotic factors
non living components of an ecoystem tht affect other living organisms .
bioic faxcors
environmental factors associted with living organissms in an eocysem =th ffect eachother , predation , disease .
componentd of an ecosytem and their meaning
HABITAT - the place where an organism lives.
POPULATION - all organisms of one species who live in the same place at the saeme time and can canbreed together .
COMMUNITY - all the population of diferent species who live int he same places at the saeme time , nd who can itneract with eachotehr .
what is a niche ?
the role of each species in an ecoystem .
-difficult to defien niche entirelybecause each organisms interacts with both living nd non-liiving things .
impossible to dra line of ecosytems . but closed eseir to udnersand .
give a couple of examples of biotic factors (1)
-producers plants ( and some photosyntheitc bactiera ) , which supply chemical energy to all other organsims .
-consumer (primar consumer ( are herbivores ,w hich feed on palns ,a nd which are eaten by crnivorous secondary consumers . Thee in turn are eenby carnivorous tertiary consumers .
give a couple of exmples of biotic factors (2)
decomposers (bacteria fungi and some aniamls ) feed onw ste mterial or dead organisms .
-because these components of the ecostem reqruie thier own source o material and egergy , they can affect other organisms’ food uspply . They can also be resposnible for predation and disease .
give a couple examples of abitoic factors
-describe the effect of the non-living componens of an ecosytems . Ph relatie humdiity temperatures and the cocnentration of polluatns are all examples .
-these can vary in space and time ,s cuh fcors could also include disturbance to he ecyosyem by other ctors such as turblence an dstorms .
give a couple of abiotic factors (2)
abitoic factors may also be infleucned by the bitioic components of the ecoysem .
-For example , in a rainforest , forest canop infleucnes the temperture and huidity of the ecosytem .
abiotic curve shown in figure 2 , explain
a generalisedcurve deplicing he efffect of an abitoic facor on an organisms activit .
-the abitioic factor could be PH tempeature or any varibale tha has some sore ot optimum level and where there are lethal levels at both extremes ..
what haooens when there is not a lethal leel at both extremes ?
an organisms resposnes plotted differnl ,, fro exmple at low elvels of pollutants ,a norganisms may survive without any detrimental effect , but a high level sthe pollutants maybe lethal .
ecosytems are dynamic why ?
because hey change nonlviign eleemnts change and lviign elemnts forwo and ide .
ecoystem lving thing inerct with environemnt , any small chances can effect one nother for example . predtors poplation size oes up , prey population fo down , ntirogen levels ins oil affect popualtion sies of plns .
-ntiogen fixiing palnts row sucessufly in nw2 eficien tsoil btu affect htie renviornment
one type of change in ecoystem affecting population size CYCLIC CHANGES
these changes repat themselves ina rhythm , for example movmemnts of tifes and changes in day length are cyclic .
-The way in which predaor and preys pecies fluctuate is cclic .
second tyoe if change in ecoystem direcrional changes
these changes are not cyclic heyg o ino ne directiona nd tend to last longer than the lifetime of orgasims withint he eocystem .
-woton such change , particualr variables continue to incrase or decrease ( examples incldue t=depostin f silt in an estuary )
third type of change in ecoystem - unpredictbale / errtic changes
these have no rhythm and no constant direction . For example , such changes , may incldue the effects of lightning or hrurricanrs .
-living thing respon to changes ine coystme so small mammals mayhiebrnte due to rhyyhtmc fo rexample .
Biomass transfer
transfer of biomass from one trophic levels to another .
trophic level
the level at which na organisms feeds in a food chain
energy and materials in an ecosytems
materials re constanlt recyled within an ecoystme nutrient cycles sucha s the nitorgen cycle and crbon cycle re good eamples energy is not recyled it lows throuhh the ecosytem.
how is energy interchanged in plnts ?
Eneergy captured in plants in photosntehssis to produce organic molecules like glucose from warer and carbondioxide .
-such energyis rlesed from glucose during respiration .0
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what are the products of photosyntheiss used for >
-they are not onl used immdeiately for resprition , but incorporated into tissued an organs (celluose - th ebuilding block of plant cell alls - is made up of large number of glucose moelcules )>
-mineral ions are also absrobed through plant root .
what happens to the plants biomass and how doe sthe biomass transfer between all the componenet s
-together , the organic components (such as glucose moelcue s) and inorganic components (such as mineral ions but exclding water ) .
-of the plan make up its biomass , so whena lant is eaten , its biomass is consumed by a priamry consumer .
how is changes in biomss tracked .
topric levels .
give me one reason why biomass is lost from the trophic elvel
t each trophic level , living organisms need energy to carry out life processes .
-respiration , releases energy from organic moelcules such a s glcuose .
-some of thisw enegry is evenutally convered to hea and materials are lost in carbondxoide and water.
another reason wh biomass i slost at ech level .
-biomass is also ost froma food chain in dead organisms and waste material , which is then only avilable to decomposers sucha s fungi and bacteria .
-this waste material also includes parts of nimals nad plan that cannotbe digested byc onsumers such as bones and hair .
Where is biomss less ?
t higher levels of the food chain . When the orgaisms in a food chaina re baout the sme size this means there will be ewer consumers at hhigher levels .
-ecologists draw a pyramid of numbe to represent htis number idea .
-THE ARE , of each bra in the pryamid i propotional to thenumbe rof indivuals an apporximaion for the total bomass at that levels .
-pyramids can be drawn for idnividual food chains . or fo an ecostem as w hole .
doe , counting the number of organisms always provide an accurate picture of how much biomass exists at each lrevel >
no , nd a bteer pproch is to draw a pyramid biomass here the area of each bar is proportional to the drymass of all the orgnamisms t that rophic level .
how do ecologists obtin dry mass,
organisms put ina n oven at 80 degrees until all the waer int hem has been evaporaed .
-they check this by periodically fidning the mass of the organisms .
-pobnce the mass stops reduing ,t hey can be certain tht all the waer has been removed .
but this is so destrcutvie so wet mss is used .
two equatiions tht are used to calculate the biomass transfer ?
page 273 .
What is productivity
The rate at whuch the production of new biomass produces .
What is gross primary productivity
It is the rate at whuch plants convert light energy into chemical energy through photosynthesis, even at the start of a food cahain , this is inefficient because photosynthesis produced glucose m entry of biomass into the food chain is also inefficient .
humans can manipulate enviornmental factors to do wht
to make energy conversion mroe eficent , reuce energy loss , and increase the amount of biomass which is incoporated into plants .
light levels limimt the raate of phottsytheisis and hence production of biomasss .
some crops are planted early to provide a logner gorwing season , to harvest more light other are feoqn under light banks
drought resistnt crops
water is a reactant in [hotosynthesis when glucose is prodcued .
growing plant in greenhouse
provide a warmer temperature , increasing the rate of photosyntheiss and increase the rate of photosynthesis and increase the rate of production of biomass . planting field crops early to provide a long growing season also help to avoid the impact of temperature on final yield . for example , winter wheat has a logner growing seaso that spring wheat .
lack of available nutrients slow the rate of production of biomass , through photosytnhesis
Crop rotation can help growing a different crop in each field on a roational cycle . This stops the reduction in soil levels of inorganic materials such as nitrate or potassium . including nitorgen -fixing crops .
fungal diseases reduces biomass
fungi cause root (reducing water absoprtion ) , , damage xylem vessles (interfering with water transport ) , danage foliage through wilt , blight or spotting (interfering wih phototsyhteiss directly ) , damage phloem tues .
-FAMER SPRAYS COPS with fungicides , many crops have been bred to resist fungal infections .
-POTATOES , Have been geentically modfiied to resist potato blight .
competition from weed for light , wter and nutrients
competition from weed for light water and nutrients reduce a crops NPP , farmers uses herbicices to kil weeds . the herbicide suallhy bidns to an ezyme stopping it from working , and frequnently leading to a toxic build-up of the enzyme;s substrate .
improving secondary productiivity (1)
transfer of biomass between trophic level is inefficent ,
PRIMARY CONSUMERS - do not make full use of plant’s biomass - some plants and they do not digest everything they eat (such as cellulose ) , egesting a lot of it in their faeces .
improving secondary productivity (2)
even when food is digested absorbed much of it is respired , with only a small amount contributing to an increase ,, in biomass , and being available , to the next consumer int he food chain ..
how human manipulate nergy transfer (1)
a young animal invest a large proportion , of its energy into growth than an adult . Harvestign animals just adulthood minimimsed loss of energy from the food chain .
humans manipulate energy tranddsfer (2)
selective breeding has been used to produce improved animal breeds with faster ggroth rates , increased egg production nad increased milk production .
humans manipulate energy transfer (3)
animals may be treated with antibiotics to aovid unecessry los of neegry to pathogens and parasites .
how to mammals bird waste lot of energy
finding food and keepign their bdoy temperatures stables zeroo grazing pig to maiminse nergy allaocated to msucles stopping animals from moving out .
although transfer of energy
mammals and brids waste a lot of energy fidning food food and keeping their body temp stable . zero grazing for pig nd cattle farmiming mazmises energy allocated , to msucle (mest ) , by stopping the farming suppling , food to them and by keeping the environment temperagture cconstant .
although transfrr of energy
from producers to consumer is inefficent ,a nd grain , could be used to feed humands directl opposed , to feeding cattle or pigs first , in some infertile reas grain cannot be ggrown but animals can surivve , for example sheep often live mountainsides producing food or humans
recycling within ecosystems
indicaes how energy and materials are lost from a food chain when living things exrete waste or die . This dead and waste organic material can be broken dwon by decomposers - microorganisms such as bacteria and fungi .
steps in saphrotic decompostion are
bacteria and fungi invovled decomposition feed in a different way from animals . They feed saprotophically so they are described as saprotrophs . They steps in saprotrphic decompostions are
1.saprotrophs secrete enzymes onto dead and waste material ..
2. enzymes digests the material into small moelcules which are then absorbed into the saprotrophs body .
steps in saphrotic decompostion are (2)
- having been absoorbed , the molecules are stored or respired to relase energy .
what happens if bacteria and fungi did not break down dead organisms
energy and valuable nutreints would remain , trapped within dead organisms , , by digesting dea and waste material mcirorgansisms , obtian a supply of energy to say alive and trapped nutrientarre recycled .
microranisms
have a particularly important role to play cyclig carbo and nitrogen within ecoystems .
recycling nitorgen
living nitorgen then to make porteins and nuccliec aaicds , firgure 2 shows how nitogen atoms are ccled betweenbiotic nad abitoic components of an ecostems , Bcteria are invovled in AMMONIFICATION ITROGEN FIXATION , nitrification dentrifiction .
nitorgen fixtion
although ntogen gas make up 79 percent of the earth’s atmosphere it is very unreactive . This means it is impossibled for plants to use it directly (even thoguh it is so abundant ) . Instead , plants need a suppply of fixed ntoegen such as ammonium ion or nitratie ions . Nitorgens fixation can occur ehrn lighting dtirkrd ot hrough the haber process only account for about 10 percent arpidm tjr wpr;d /
nitrogrn fixing bacteria
nitorgen fixin bacteria supply he rest of the fixed nitorgen . azobacter srre bacteri that lvie freely , in the soil and fixed niotgrn fixation nitrification and denitrificiation .
how is ammoniification and nitrification
ammonium ions are released through ammonification by bacteria invovled in patrefaction , of proteins found in dead or waste organic matter . Rather than getting thier energy from such sunlght like phottautropuic bacteria alage and planrs .
I’m modification and modification
Some chemoautotrophic bacteria in the soil nitrous is over a bacteria obtained by oxidising ammonium ions nitrates, while others (nitro bacteria obtained by oxidising nitrates into nitrates. These prices are called notification.
What does oxidation require?
Box station requires us therefore these reactions only happened well aerated foil.
Nitrates can be absorbed from the soil by plants are used to make mix type bases for nucleic acids amino acids ((for proteins).
What is denitficaitin
Read notification is when bacteria converts nitrate back to nitrogen gas. And the battery involved under anaerobic conditions such as water soils, they use nitrates as a source of oxygen for their respiration, and produce nitro and gas and nitrous oxide.
Learning tips for nitrogen cycles
Ensure you distinguish the process of light and fixation conversion of atmospheric, largest nitrate to ammonium, notl notification (oxidation of ammonium nitrate and nitrate nitrate, and denitrification nitrates to
How is carbon recycled between the biotic and a biotic components of an aphid system?
Call Ben is also cycled by the process of respiration photosynthesis, with conduct of being the main vehicle for the cycling of carbon dioxide between biotic and abiotic and have a cycle. Adam was, plants and micro organisms come outside. Organism is a particularly important and decomposition of dead organisms and waste.
Terrestrial plants, how do they use carbon dioxide?
They use carbon dioxide in photosynthesis as well as aquatic plant you dissolve carbonates
How is carbon exchanged?
Carbon is exchanged between the air and water and carbon dissolves in water and then reacts to form carbonic acid. Carbon also enters rivers and legs from weathering or limestone and talk in the form of hydrogen carbonate.
What has the combustion of fossil fuel is done?
The combustion of fossil fuels has increased across the law century that the balance of the carbon cycle changing atmosphere carbon dioxide levels are higher. This is the change that is responsible for global warming.
what is a climax community
the final stable community that exists after the process of succession has occured .
what is a pioneer species
the species that begin the process of succession , often colonising an area as the first living things there .
wht is deflected succession
happes when succession is stopped or interfered with , such as by grazing or when a lawn is mowed .
what is succession
progressive change ina community of organisms over tie .
chaning ecocystems
any change in a community of organsims can cause a change in their hbittat . Any change in a habitat can also cause a change in the make-up of the community . These ideas , can explain why gradual directional changes happen ina communitu over time . Such a process of directionl change is called succession .
part one of successio process
algae and lichens begin to live on the bare rock . This is called a pioneer community .
part two of the succession
eroion of the rock and a build up of dead rotting organic material produce enough soil ofr larger plants , like mosses and ferns t gorw . These replace or succeed , the algae and lichens .
part three of the successions
in a similar way , larger plants succeed these small plants , until a final stable community is reached . This is called a climax community . Int he UK , climae communities are often woodland communities .
does succession always start from bare ground ?
secondary successions take place on a previosul colonised but distubed or damaged habitait .
how does sand dunes do succesion dispaly all stages at teh sme time
look at the beach and sand dunes , because se deopsiits sand on the beach , the sand nerest to the sea is deposited more recenlty thn the sand furhter away .
-This means tht the sand just above the high water ark is at the start of the process of succesion , whereas the sand much further away already hoss it climx communty . By walking up the beach and throuhg the dunes , it is posinle to see ach stage in the process of succesion .
first stage of succession
pioneer species like sea rocket , and pricklysandwort , colonise the sand just mabove the high waer mark . These cn tolerate being sprayed with salty water , laock of fesh water nd unstable sand .
second stage of succession
wind blown sand builds up around the base of these plants , forming mini sand dune . s plants , die and decay , nutreints accumualte in this mini dune . As the udne gets bigger , plants like sea sandwort nd sea couch grass , colonise it .. Because sea couch grass has undergounds tems it helps to stbulise the snd .
third stage of succession
wiht more stability and accumulation of more nutrients , plants like sea spurge and marram grass , start to grow . Marram grass is special ; its shoot trap wind-blown sand , and as the sand accumualgtes the shoots grow taller to stay above the growing dune , trapping more sand in the process .
fourth stage of succession
as the sand dune and nutrients build up other plans colonise the sand , . Many are leguminous such as hare foots loer , whihc converts nitorgen into nitrate ,w ith nitrate available more psecies colonise the dunes lke sand fescue and vipers bugloss ,w hih stbilise them further .
what is deflected succession
the landscape in the uk is hevil ifnuelcuned by agriculture ,t herefore it can be difficult to work out hether a aprticulr location has reached its clima community
deflecrd succesion includes grazing burning fertlsier exposer to excesive winds , humana cvitivyt .
first type of data collected with quadrat
presence or abscence of each speicies (distributoin ) . Usually at least 50 percen of the plant needs to be isnide the quadrat to count .
second type of data collected with quadrat
number of inidividuals (the abunance ) of each species - either estimate dor ocunted . For some plants , like grass and moss , it is difficult to count idividuals so ecologists tend to estimate prcentgae ocer .
how to calcuale populion size of a pecies
mean number of idniduals of the species in each quadrat / fraction of the otal habitat area covered by a single qudrat .
What is gross primary productivity
It is the rate at whuch plants convert light energy into chemical energy through photosynthesis, even at the start of a food cahain , this is inefficient because photosynthesis produced glucose m entry of biomass into the food chain is also inefficient .
