Module 6

• Change in sequence of base pairs of DNA
• substitution, deletion or insertion

When only one nucleotide is affected

• No effect - no effect because normally functioning proteins are still synthesised ~ silent mutation, or new amino acid has similar properties to the normal one
• Damaging - phenotype of organism negatively affected
• ~ protein no longer synthesised/functional 
• Beneficial - useful protein synthesised that results in a benefit

• Spontaneously during DNA replication
• As a result of mutagens:
• -free radicals
• -radiation e.g X-Rays 
• -viruses e.g insert viral DNA into a genome changing base sequence

• Silent ~ do not change any proteins or the activity of proteins synthesised
• -no effect on organism's phenotype
• -can occur in non-coding regions (introns), or code for same/similar amino acid
• -may change primary structure of protein but overall structure is the same
• Nonsense ~ result in a stop codon instead of coding codon
• -results in shortened protein
• -usually non-functional 
• Missense ~ incorrect amino acid(s) incorporated
• -could be silent, beneficial or harmful
• -conservative mutation when new amino acid has similar properties to original
• -non-conservative mutation when new amino acid has different properties to original

• Deletion: a section of chromosome breaks off & is lost within cell
• Duplication: sections get duplicated
• Translocation: section of one chromosome breaks off and joins another non-homologous chromosome
• Inversion: section breaks off, is reversed, & joins back on

• Transcriptional: genes turned on or off
• Post-transcriptional: mRNA modified regulating translation and therefore the proteins produced
• Translational: translation can be stopped or started
• Post-translational: proteins modified after synthesis

• Chromatin remodelling
• Histone modification
• Lac operon

• Heterochromatin: tightly wound DNA ~ chromosomes visible during cell division
• Euchromatin: loosley wound DNA ~ interphase
• RNA polymerase cannot access the DNA when it is tightly wound, so transcription does not occur
• -ensures proteins needed for cell division are made during interphase
• -energy is not wasted synthesising proteins during division

• Histones: positively charged
• DNA: negatively charged ~ so coils around histones
• Histones can be modified to alter the degree of their + charge
• -addition of acetyl groups (acetylation) or phosphate groups (phosphorylation) reduces + charge so DNA coils less tightly
• -addition of methyl groups (methylation) makes histones more hydrophobic so they bind more tightly to each other and DNA coils more tightly

• Regulator gene: codes for a repressor protein that prevents the transcription of structural genes by binding to the operator and preventing RNA polymerase from binding to DNA on promoter
• -"down regulation"
• Lactose present: if lactose is present it binds to repressor protein, changing its shape so it can no-longer bind to the operator
• -RNA polymerase can now bind to promoter and the 3 structural genes are transcribed & enzymes synthesised
• 

• When CRP (cAMP receptor protein) is bound to cAMP
• Rate of transcription is increased

• Transport of glucose into E.coli decreases levels of cAMP, reducing transcription of genes responsible for metabolism of lactose
• -if both glucose and lactose are present, glucose is the preferred respiratory substrate that is metabolised (easier to metabolise)

• RNA processing: pre-mRNA is modified forming mature mRNA
• - cap added to 5' end
• - tail added to 3' end
• - both help to stabilise & delay degradation of mRNA in cytoplasm
• - splicing ~ RNA cut at specific points, introns removed (non-coding DNA) & exons joined together. (occurs within nucleus)

• RNA editing: nucleotide sequence of mRNA altered 
• -addition, deletion or substitution
• -giving same effect as point mutation
• -increases range of proteins produced from single mRNA molecule or gene

• Regulation of protein synthesis
• Degratation of mRNA: the more resistant the molecule the longer it will last and a greater quantity of protein is synthesised
• Binding of inhibitory proteins to mRNA: prevents it binding to ribosomes & stops protein synthesis 
• Activation of initiation factors: aid the binding of mRNA to ribosome

• Modifications of poteins produced 
• Addition of non-protein groups: e.g. carbohydrate chains, lipids or phosphates
• Modifying amino acids: and therefore formation of bonds e.g disulfide bridges
• Folding or shortening of proteins
• Modifications by cAMP: e.g in lac operon cAMP binds to cAMP receptor protein increasing rate of transcription of structural genes

• Group of regulatory genes found in animals, plants and fungi
• Contain a homeobox
• -section of DNA 180 base pairs long
• -codes for protein 60 amino acids long that is highly conserved
• -protein binds to DNA & switches other genes on/off

• Group of homeobox genes responsible for correct positioning of body parts in animals
• Order of Hox genes on chromosomes is the order in which their effects are expressed
• Animals are segmented
• E.g Hox genes in the head control development of mouthparts
• E.g Hox genes in thorax control development of wings, limbs or ribs

• Radial: have a top and bottom but no left/right. E.g jellyfish
• Bilateral: have head and tail, left and right. Seen in most animals
• Asymmetry: no lines of symmetry. E.g sponges

• Mitosis: results in cell division and proliferation
• -increases number of cells leading to growth
• Apoptosis: programmed cell death
• -removes unwanted cells/tissues
• -cells undergoing apoptosis can release chemicals to stimulate mitosis in other cells ~ leading to remodelling of tissues
• -e.g webbing between fingers

• Stress: upsets homeostatic balance within organism
• -due to external factors E.g. temperature/light
• -or internal factors E.g release of hormones or psychological stress
• Affects expression of regulatory genes which control cell cycle and apoptosis

Examples: drugs ~ thalidomide prevented normal expression of a particular Hox gene resulting in shortened limbs

• Chlorosis in plants
• ~ the yellowing of leaves due to lack of chlorophyll
• -large quantities coded for genetically in most plants
• -lack of light ~ plants stop its production to save resources
• -mineral deficiencies ~ e.g lack of Iron/Magnesium which act as cofactors to enzymes
• -Virus infections ~ interfere with metabolism of plants
• Animal body mass
• -genetic factors
• -amount & quality of food & exercise
• -diseases

Continuous and Discontinuous (of Discrete)

9:3:3:1

• Occurs when two different alleles for a gene are equally dominant.
• Both are expressed in the organism's phenotype

• Letter chosen to represent the gene
• Different alleles represented using a second letter in superscript
• e.g. C^RC^R and C^WC^W C^RC^W for red, white & pink flowers

Shows inheritance of two different characteristics caused by two different genes

• Random fertilisation of gametes
• Genes being studied may be on the same chromosome ~ linked genes ~ inherited together

• Genes are located on the same chromosome
• Therefore inherited as one unit
• -unless there is crossing over & they get separated 
• Autosomal linkage

Recombinant offspring

• A measure of the amount of crossing over that happens during meiosis
• Recombination frequency = (no. of recombinant offspring) ÷ (total number of offspring)

• 50% indicates no linkage
• Less than 50% indicates gene linkage ~ random independent assortment is hindered

Less crossing over due to genes being closer together means a smaller value

• Measures the size of the difference between actual results and expected results, and whether they are statistically different
• Null hypothesis ~ there is no significant difference between expected and observed values
• Degrees of freedom are calculated as n-1 (n= no. of categories)
• ☆ X² less than critical value there is no significant difference
• ☆ X² greater than or equal to critical value there is a significant difference. Null hypothesis rejected.

• Interaction of genes at different loci. 
• e.g. gene regulation - as regulatory genes control the activity of structural genes

• -hypostatic
• -epistatic

• Dominant epistasis - if a dominant allele results in a gene having an affect on another gene
• Recessive epistasis - presence of two recessive alleles cause a gene to have an affect on another gene

The sum of all the genes in a population at any given time

The relative frequency of a particular allele in a population

p + q = 1

• p = frequency of dominant allele
• q = frequency of recessive allele

• "In a stable population with no disturbing factors, the allele frequencies will remain constant from one generation to the next and there will be no evolution."
• -allows us to measure evolutionary changes when they occur

p² + 2pq + q² = 1

• p² = frequency of homozygous dominant genotype in population
• 2pq = frequency of heterozygous genotype in population
• q² = frequency of homozygous recessive genotype in population

• The population is large and isolated
• Random mating
• No mutations
• No selection pressures

These conditions virtually never occur in a natural environment

• Mutation: necessary for existence of different alleles
• Sexual selection: leads to increase in frequency of alleles that code for mating success
• Gene flow: movement of alleles between populations. E.g immigration and emigration
• Genetic Drift: In small populations the presence of a new allele has a much larger impact
• Natural Selection: leads to increase in frequency of alleles that code for beneficial characteristics

• Limiting Factor: limits or decreases the size of a population
• Density-dependent: dependent on population size. E.g competition, predation, communicable disease
• Density-independent: affect populations of all sizes. E.g climate change, natural disasters, human activities

• A large reduction in population size that last for at least one generation
• Gene pool and genetic diversity greatly reduced

• Genetic Drift
• As small populations have a much smaller gene pool than the original population
• Alleles carried to the new population become more frequent

Normal distribution

• Stabilising
• Directional
• Disruptive

• The norm or average is selected for
• -increase in alleles for average characteristics
• -reduces frequency of alleles that code for extreme characteristics 

E.g birth weight of babies ~ underweight babies are more at risk of infections, while heavy babies have more difficult births. Therefore the babies most likely to survive have an average weight

• Occurs when there is a change in the environment and the norm is no longer the most advantageous 
• Allele frequency shifts towards more extreme phenotypes (positive selection) 

E.g colour of peppered moths

• Extremes selected for
• Norms selected against

E.g Darwin's finches

• Happens when members of a population are separated
• e.g by a river or the sea ~ geographically isolated
• Different selection pressures result in different adaptations 
• Founder effect

• E.g Darwin's finches
• -adaptive radiation took place leading to the rapid organism diversification and finches with many different shaped beaks specialised for the different food sources on the islands

• Occurs within populations that share the same habitat.
• More common in plants - members of two species interbreed forming fertile offspring that have different no. of chromosomes to parents, so can only breed with other offspring. Stops gene flow

• E.g Fungus farming ants:
• some parasitic ants have developed from members of the colony, and now feed on the farmed fungus

• E.g Naked mole rats:
• only interbreed with those that live in the same soil type
• however do come into contact with each other
• likely to form different species

• Prezygotic barriers: prevent fertilisation 
• Postzygotic barriers: often produced as a result of hybridisation, reduce viability or reproductive potential of offspring

• Plants or animals are selected for breeding because they have desirable characteristics 
• Inbreeding is used - offspring with the most desirable characteristics are selected and bred
• Repeated over many generations resulting in changes to allele frequency

Gene pool is limited → genetic diversity reduced → population's ability to adapt reduced

Many genetic disorders are recessive, and breeding closely related organisms results in two recessive copies being inherited resulting in the disorder. (e.g cystic fibrosis)

Store biological samples ~ e.g sperm or eggs.

• Used to increase genetic diversity via outbreeding
• ~ breeding unrelated/distantly related individuals to reduce occurrence of homozygous recessives & increases ability to adapt

• Wild type alleles: The allele coding for the most common or normal characteristic in a population
• Mutants: other forms of the wild type allele that result from mutations

Short sections of DNA that are repeated over and over

• Minisatellite: 20-50 base pairs long. Repeated 50 - several hundred times
• AKA VNTRs ~ variable number tandem repeats
• Microsatellite: 2-4 base pairs. Repeated 5-15 times
• AKA STRs ~ short tandem repeats

• Satellite DNA appears in the same places on the chromosomes
• But individuals have different lengths of repeats
• Closely related individuals have more similar lengths of repeats

• 1. Extracting DNA
• -only a tiny sample needed since PCR can be used to replicate it
• 2. Digesting the sample
• -DNA cut into small fragments
• -restriction endonucleases
• -cut (twice ~ both strands) at a restriction site
• 3. Separating DNA Fragments
• -electrophoresis
• -gel submerged in alkali to separate double strands
• -single-stranded fragments then transferred onto a membrane
• 4. Hybridisation
• -Radioactive or Fluorescent DNA probes added in excess
• -complementary DNA/RNA to known fragments
• -Bind to fragments to 'label' them
• 5. Seeing the evidence
• -X-ray images taken of paper/membrane
• -Or placed under UV light (depending on lebels used
• -Fragments give a pattern that is unique to every individual (except identical twins)

• DNA fragments put into wells in gel
• Buffer solution maintains constant pH
• Electric current passed through gel
• DNA fragments move from negative cathode to positive anode
• -Due to DNA's negative charge ~ phosphate groups
• Gel has mesh like structure ~ resists movement of fragments
• Smaller fragments able to move faster so go further in set time

• Gel put in alkaline buffer to denature DNA & split fragments into single strands
• Southern blotting ~ strands transferred to membrane

DNA fragments of known length used as comparison

Polymerase Chain Reaction

• 1. Separating the strands
• 90-95°C denatures DNA by breaking hydrogen bonds therefore separating the strands

• 2. Annealing of Primers
• 55-60°C primers bind to the ends of DNA strands

• 3. Synthesis of DNA
• 72-75°C DNA polymerase - Taq polymerase - adds bases to the primer, building complementary strands 
• Double strand identical to original is formed

• Forensic Science ~ identifying a criminal
• Paternity Testing
• Identifying the species of an organism
• Show evolutionary links
• Identifying individuals at particular risk of developing certain diseases

Determining the precise order in which nucleotides occur within a DNA molecule

1. DNA mixed with primer, DNA polymerase, excess of normal nucleotides, and terminator bases

2. Placed in Thermal Cycler (used for PCR). 96°C DNA separates into 2 strands. 50°C Primers anneal

3. 60°C DNA polymerase builds up new DNA strands by adding nucleotides to complementary bases

4. Each time a terminator base is incorporated (instead of normal nucleotide), synthesis stops. This happens randomly, resulting in many different fragments. After many cycles, all possible fragments are made

5. DNA fragments separated by length by capillary sequencing & fluorescent markers on terminator bases identified using a laser to tell each colour ~ therefore the sequence of bases

6. Order of bases is the complementary strand & is used to work out sequence of original DNA strand

• Stops DNA synthesis.
• E.g an A terminator stops synthesis where an A base would be added
• Have fluorescent tags
• Less terminator bases added than normal nucleotides so that all possible DNA fragments are found

• Past: 
• -time consuming
• -radioactive labelling 
• -gel electrophoresis on single gel
• -manual 

• Capillary method:
• -similar to gel electrophoresis but in a capillary tube

• Now:
• -Faster & more automated
• -High-throughput sequencing processes
• -Takes place on plastic slide ~ 'flow cell'
• -Integrated with computer technology
• -Less costly

• Bioinformatics: Development of software to organise and analyse raw biological data in order to make sense of it
• -algorithms
• -mathematical models
• -statistical tests

• Computational Biology: uses data from bioinformatics to build models of biological systems that can be used to make predictions
• -e.g. working out 3D structure of proteins

• Doctors can find the source of an infection
• Doctors can identify antibiotic resistant strains of bacteria to ensure treatment is effective and preventing spread of antibiotic resistance
• Track the progress of an outbreak
• Identify regions in genome of pathogen that may be useful targets in development of new drugs

• "DNA barcoding"
• Genome analysis acts as a tool in species identification by comparison to a standard sequence for the species
• Identify sections of the genome that are common to all members of the species so comparisons can be made
• -For animals this is a section of mitochondrial DNA in the gene for cytochrome c oxidase
• -regions of DNA from chloroplasts used for plants
• -Not suitable (yet, maybe ever) for fungi & bacteria

• Finding evolutionary relationships
• -basic mutation rate calculated & scientists can calculate how long ago two species diverged from a common ancestor

• "The study of amino acid sequencing and an organism's entire protein complement"
• As a gene may not always code to produce just one type of protein
• -introns and sometimes some exons removed from pre-mRNA
• -spliceosomes may join exons up in a variety of ways
• -proteins get modified after they are made

"The design and construction of novel artificial biological pathways, organisms or devices, or the redesign of existing natural biological systems"

• Examples:
• -Genetic engineering 
• -Use of biological systems in industrial contexts ~ e.g use of fixed or immobilised enzymes or the production of drugs by microorganisms 
• -synthesis of new genes to replace faulty ones ~ e.g. in developing treatments for cystic fibrosis
• -synthesis of an entire new organism ~ create an artificial genome

• An organism that carries a gene from another organism
• "A GMO ~ genetically modified organism"

• Isolating desired gene
• Placing it into a vector
• Transferring the vector

• Restriction endonucleases
• -cut required gene from DNA
• -many make an uneven cut leaving 'stick ends' ~ useful in inserting the gene into the DNA of another organism

• The formation of recombinant DNA using vectors
• Plasmids:
• -once a plasmid gets into the host cell it can combine with the host DNA to form recombinant DNA

• Plasmid cut by same restriction endonuclease to give complementary sticky ends
• Fragment inserted
• DNA ligase forms phosphodiester bonds between sugar and phosphate groups on the two strands of DNA ~ joining them together

• Genes which provide scientists a way of telling if the insertion of the plasmid and DNA fragment was successful.
• Usually two marker genes:
• -one contains the region where the DNA fragment is added ~ so no longer works if insertion is successful
• -the other shows that the host cell successfully took up the plasmid DNA

• Examples:
• antibiotic resistance
• fluorescence 
• production of an enzyme that causes a change in substrate colour

Process called transformation

• Culture bacterial host cells and plasmids in calcium rich solution and increase temperature
• -bacterial membrane becomes more permeable & plasmids enter

• Electroporation (another type of transformation)
• -small electrical current applied to bacteria
• -makes membranes porous so plasmids move into cells
• -also used on eukaryotic cells

• Tiny electric currents applied to two cells
• -fuses cells and nuclear membranes
• -forms polyploid cell containing DNA from both
• -useful in GE of plants
• -useful in production of monoclonal antibodies

• Prokaryotes:
• -easiest
• -done to produce many different substances useful to us ~ e.g. hormones or antibiotics

• Plants:
• -easiest eukaryote to GE
• -electrofusion ~  involves removal of cell wall, fusion, hormones to grow new cell wall, production of callus and then production of many cloned transgenic plants
• -OR use a bacterium that causes tumours in plants ~ desired gene placed in bacterium, carried directly to plant cell DNA, transgenic plant forms callus, the cells form which can be used to grow new individual plants

• Animals:
• -hardest, especially mammals
• -cell membranes less easy to manipulate

• PROS
• -modified to produce many useful substances in large quantities. ~ useful in medicine. E.g. Insulin
• -GM microorganisms used to store a living record of DNA of other organisms in DNA libraries ~ e.g. sections of human genome for the HGP which can be later used for further study
• -Industrial processes

• CONS:
• -Biological warefare ~ GE of pathogens to make them resistant to all treatments, or more virulent

• PROS:
• -help feed ever-growing population
• -could overcome environmental issues such as excess carbon dioxide and pollution
• -insect resistance ~ SOYA → gene inserted so they produce protein toxic to insects → reduces need for expensive 
• -Disease resistance
• -Herbicide resistance
• -Extended shelf life
• -Altered growing conditions
• -Better nutritional value

• CONS: 
• -Insects may become resistant to pesticides
• -Disease resistance may spread to weeds → superweeds
• -Reduced biodiversity if herbicides are overused to destroy weeds
• -Reduced commercial value due to extended shelf life
• -allergies to proteins in GM crops

• Patents may prevent people in LEDCs form using the technology
• -since they have to pay whoever came up with it
• -The people who need it most cannot use it

• Resistance ~ giving livestock resistance to certain diseases
• Faster Growth ~ genes from faster growing animals inserted so GM animals (e.g Salmon) produce more growth hormone and grow faster

• Pharming:
• Creating animal models
• -addition or removal of genes so animals develop certain diseases and can act as models for treatment developments
• Creating human proteins
• -introduction of human gene for medically required protein that bacteria are not capable of making
• -put in fertilised cow/sheep/goat egg
• -transgenic animal born
• -produces milk containing desired human protein

• Should animals act as models for human disease?
• Is it okay to put human DNA into animals?
• What if it causes harm to the animal?
• Does it reduce animals to commodities?
• Is their welfare compromised?

• Somatic cell gene therapy
• Germ line cell gene therapy

Replaces mutant allele with healthy allele in affected somatic ~ body ~ cells

• Some difficulty in getting the alleles into the affected cells, getting plasmids into nucleus of cells, and maintaining expression of the allele 
• -since somatic cells only have a limited life and are eventually replaced from stem cells which contain faulty allele
• Temporary
• Still pass mutant allele onto offspring

Inserting healthy allele into germ cells ~ usually eggs ~ or embryo immediately after fertilisation (as part of IVF)

• Gives healthy individual
• Would pass on healthy allele to offspring

• Currently illegal in many countries
• -impacts unknown
• -against unborn individual's consent
• -could give rise to 'designer babies'

All of the living and non-living factors that interact within a given area

The efficiency at which biomass or energy is transferred from one trophic level to another

• (energy/biomass available after the transfer) ÷ (energy/biomass available before the transfer) 
• (all x100)

Gross production - respiratory losses

An organism that feeds on and breaks down dead plant/animal matter, turning organic compounds into inorganic ones

Saprotrophs

• Detritivores 
• e.g. woodlice and worms

• atmospheric nitrogen N₂ combined with H₂ to form ammonia NH₃
• -can be absorbed and used by plants

• Nitrogen fixing bacteria contain nitrogenase
• Azotobacter live in soil
• Rhizobium live inside root nodules and exchange nitrogen fixation for carbohydrates form the plant

Process by which ammonium compounds in soil are converted into nitrogen-containing molecules that can be used by plants

• Nitrifying bacteria 
• Oxidation reaction (needs well aerated soil)
• 1: Nitrifying bacteria ~ Nitrosomonas ~ oxidise ammonium compounds into nitrites NO₂^-
• 2: Nitrobacter (another genus of nitrifying bacteria) oxidise nitrites into nitrates NO₃^-

• Denitrifying bacteria convert nitrates in soil back to nitrogen gas in anaerobic conditions. E.g. waterlogged soil
• Use nitrates as energy source for respiration

Process by which decomposers convert nitrogen containing molecules in dead organisms/waste into ammonium compounds

Night ~ when plants are not photosynthesising

Warmer water can hold less dissolved CO2

• Progressive replacement of one dominant type of species/community by another in an ecosystem
• until stable climax community is reached

• Primary: area of new land/newly exposed. No soil or organic matter to begin with
• Secondary: Soil present with no plant/animal species. E.g after forest fire

seral stage

At each stage key species are identified that can change the abiotic factors

• Pioneer community
• Intermediate community
• Climax community

The organic component of soil from decomposition of organisms from the pioneer species

Mid-succession

• Human activities can halt natural succession
• Plagioclimax ~ final stage formed as a result of succession being halted artificially
• e.g. agriculture & conservation

• Esitmated population size = (number of individuals in first sample x no. of individuals in second sample) ÷ (Number of recaptured marked individuals)
• Lincoln Index

• 1. Slow growth. A few individuals are breeding
• 2. Exponential growth. Greater no. of breeding individuals. No constraints on population size
• 3. Stable state. Carrying capacity is reached. Fluctuates around point. Birth rate = death rate

• Immigration - moving into a new area, increasing its population
• Emmigration - moving away from an area, decreasing its population

• Factors that affect the whole population regardless of it's size.
• E.g natural disaster

• Interspecific 
• Intraspecific

• Two species compete for a limited resource
• The better adapted one will outcompete the other
• The less well adapted species will decline in numbers

• Conservation: the maintenance of biodiversity through human action or management
• Preservation: the protection of an area by restricting or banning human interference 
• -e.g. marine conservation zones

• The process of restoring ecosystems that have been damaged or destroyed.
• -e.g. by floods or building work

• Economic - resources needed for humans to survive and make an income
• Social - people enjoy natural beauty
• Ethical - all organisms have a right to survive

Renewable resource that is being economically exploited in such a way that it will not diminish or run out

• Coppicing 
• Tree trunk cut close to ground
• New shoots develop & mature
• Harvested
• Rotational coppicing 
• -don in areas at a time to give sections time to develop and grow
• Pollarding 
• Similar to coppicing but trunk is cut higher up to prevent access by deer to the new shoots

• Selective Cutting - only take the largest trees
• Replant trees - helps ensure biodiversity, mineral and water cycles are maintained
• Plant trees at optimal distance - yield more wood
• Manage pests & pathogens

• Quotas
• Nets with certain mesh size
• Prevent fishing at certain times of year
• Fish farming

• Removal of acacia bush which was a habitat for a fly that carried disease
• Grazing limited to certain areas
• Ecotourism 
• -ensures tourism doesn't exploit natural environment/local communities
• -consults & engages w local communities 
• -ensures benefit to local people as well as visitors
• Reserve rangers to prevent poaching
• Scientific research projects to help understand the impacts of developments in the area
• Balance striked between human land use and wildlife

• Sustainable forest management
• -supportive government legislation
• -development of local community forestry groups which work together
• ~e.g. gaining Forestry Stewardship Council (FSC) certification, which rewards sustainable forestry

• Sustainable agriculture
• -growing multiple crops
• -growing nitrogen fixing crops
• -growing crops resistant to certain challenges ~ use of modern biotechnology and GE
• -using manure
• -growing crops in the hills

• Maintain or restore water levels
• Avoid disturbance 
• Reduce ditches
• Remove seedlings
• Controlled grazing

• Disruption of ecosystems
• -domestic animals roam loose
• -fires
• -cutting forests
• -hunting tortoises

• Measures implemented:
• -Park rangers
• -limiting human access
• -controlling migration to and from islands
• -strict control of introduced animals ~ eg pigs

• Affects:
• -global warming
• -hunting of whales, seals and fish leads to depleted stock
• -soil contamination
• -discharging of waste into the sea

• Management:
• -Antarctic treaty
• -scientific cooperation between nations
• -protection of the antarctic environment
• -conservation of plants and animals
• -management of tourism
• -designation of managed and protected areas

• National park
• Conserve & enhance natural beauty, wildlife and culture
• Promote understanding & enjoyment of the park
• Enhance social & economic communities within park

Power station built inside mountain to preserve natural beauty

• National Park Authority
• -conserves region while enabling access to visitors
• Active management of countryside
• Replanting of tree species