cloning and biotech🤖 Flashcards
explain relationship between sugar concentration falling and ethanol concentration increasing in a bacteria pop
- sugar converted to ethanal
- anaerobic respiration
- sugar undergoes glycolysis
- pyruvate forms ethanal
- NADH gives H to ethanal
- NAD regenerated
why is ethanol considered a primary metabolite of yeast
produced during normal growth
2 factors that may limit max size of yeast population
- sugar concentration falls too low
- pH falls too low
methods of immobilising enzymes
- entrapment in matrix eg polysaccharide, gelatine, activated carbon
- membrane entrapment in microcapsules or behind semi permeable membrane
- adsorption (ionic bond to solid) eg cellulose, silica
- alginate beads
- covalent bonding
benefits of immobilised enzymes
- cheaper in long run as can be reused
- enzyme separate from product so do not have to purify so save money
- immobilised enzyme works at higher temp so reaction can be faster
- can work in changed pH
4 stages of bacterial growth are
- lag phase
- log phase
- stationary phase
- death phase
what is a primary metabolite
- molecule made in or needed for normal growth
- eg glucose or ethanol
2 factors in a fermenter to maximise bacteria growth
- maintain optimum temp
- increase O2
define recombinant DNA
DNA combined from 2 sources
outline process by which a goat may be cloned
- somatic nucleus fused with empty egg cell from another goat
- by electric shock
- this cell grown in vitro
- embryo split
- embryos put in surrogates
what is ethanol used for in plant cloning
sterilising the plant tissue
the tissue sample removed in plant cloning is called…?
the explant
in plant cloning, what is the mass of cells produced called
callus
differences between TLC and gel electrophoresis
- TLC separates by solubility, GE seperates by size
- TLC separates non charged particles, electrophoresis separates charged
- dyes used in TLC, fluorescent tag in electrophoresis
- buffer solution in electrophoresis not TLC
- electricity used for electrophoresis not for TLC
how to increase rate at which bacteria take up plasmids
electroporation
in genetic engineering of e.coli why is a plasmid containing antibiotic resistance gene used
acts as marker gene to indicate which bacteria have taken up plasmid
how to use PCR to compare e.coli growth rates on cancerous liver tissue and healthy tissue
- extract DNA from cancerous liver tissue and healthy tissue
- choose primers for e.coli and DNA
- compare rate of DNA amplification
uses of dna profiling
- paternity
- forensics
- classification
why are some regions of DNA described as non coding
- introns are non coding
- not present in mature mRNA
- not translated
- regulatory genes
why do non coding regions of DNA show more variation
not selected against
describe micro propagation
- take small tissue sample from parent plant (explant)
- sterilise sample with ethanol
- put sample in sterile agar plate with nutrients and hormones
- cells multiply to form mass of identical cells called a callus
- callus is divided up and transferred to new culture medium of hormones and nutrients which causes developments of genetically identical plantlets
- plantlets into compost
disadvantage of micropropagation
- no genetic variation so susceptible to same diseases
- relatively expensive and requires skilled workers
- explants and plantlets susceptible to moulds and other diseases
- if source is infected with virus then all clones will be
what is artificial embryo twinning
many identical embryos from one developing embryo
disadvantage of animal cloning
no genetic variation
what is biotechnology
use of organisms in technology to make a useful product
what does aseptic mean
without microorganisms
list two aseptic techniques
- sterilising equipment
- hand washing
compare the two types of fermentation
batch fermentation
-nutrients and microorganisms added to fermenter at the start, products harvested at the end of fermentation
continuous fermentation
-nutrients steadily added to fermenter and products constantly harvested
why are aseptic techniques important in a fermenter
- unwanted microorganisms may grow
- these compete for food and decrease yield and may produce other products
- may be harmful microorganisms
what type of fermentation produces penicillin and why
batch
-penicillin is a secondary metabolite and only produced at a later stage
which enzyme is used to make fructose syrup
glucose isomerase
advantages of continuous fermenter
- fermenter always in use
- high yield
why is there a lag phase in growth
making proteins essential for growth takes some time
examples of natural plant clones
- bulbs eg daffodil
- runners eg strawberry
- rhizomes eg marram grass
- stem tubers eg potato
what are perennating organs
- contain stored food from photosynthesis
- can remain dormant in soil
- enable plant to survive adverse conditions
- asexual reproduction
- allow survival from one season to next
advantages of plant cloning
- faster than growing from seeds
- guaranteed good quality plants
what is micropropagation
process of making a large number of genetically identical plants from a single parent plant using tissue culture techniques
when is micropropagation used
when the desired plant:
- doesnt respond well to natural cloning
- doesnt readily produce seeds
- is very rare
- has been GM or selectively bred with difficulty
- needs to be pathogen free
advantages of micropropagation
- allows for rapid production of large numbers of desired plants
- way of producing large number of seedless plants
- culturing meristem produces disease free plants
- way of growing plants which are difficult to grow from seed
- way of increasing numbers of rare or endangered plants
examples of natural animal clones
- starfish regenerate entire animals from fragments of original
- flatworms and sponges fragment and form new identical animals
- hydra produce small buds which develop into genetically identical clones
- monozygotic twins (early embryo splits to form two identical embryos)
methods of animal cloning
- artificial embryo twinning
- somatic cell nuclear transfer
describe artificial embryo twinning
- embryo either fertilised naturally and extracted or fertilised in vitro
- while cells are still totipotent, early embryo is split to produce several smaller embryos
- embryos allowed to grow in lab then implanted into separate surrogates
- embryos develop as normal, now you have a bunch of genetically identical animals
describe somatic cell nuclear transfer
- nucleus removed from somatic cell of desired adult animal
- nucleus removed from mature ovum from different female animal of same species
- nucleus from desired adult animal is put into enucleated ovum and given a mild electric shock to fuse and begin to divide
- or the two cells are placed next to each other and electrofused
- embryo transferred to uterus of third animal
- new animal is a clone of original animal
- however mitochondrial DNA will come from ovum
advantages of artificial embryo twinning
-animals with desired traits can produce many more offspring than naturally
advantages of SCNT
- enables cloning of specific animals
- endangered animals can be reproduced
disadvantages of SCNT
- inefficient process, takes many eggs to produce, many result in miscarriage
- shortened life spans
what makes microorganisms good for biotech
- no welfare issues
- many different microorganisms which all carry out different chemical reactions
- can GM to make them produce any compound needed
- short life cycle and rapid growth rate
- nutrient requirements usually v cheap
- low temp
advantages of using microorganisms to make food
- can GM to have high protein
- not dependent on weather
- reproduce and produce protein faster than animals and plants
- no welfare issues
- production can be easily increased or decreased to match demand
- microorganisms can consume waste for energy
disadvantages of using microorganisms to make food
- microorganisms have to be separated to get product
- need sterile conditions
- some people concerned about GM
- protein needs to be purified to ensure there are no toxins or contaminants
what type of fermentation produces penicillin and why
- batch fermentation
- penicillin is a secondary metabolite produced after the exponential growth phase
- cannot use continuous fermentation as this maintains the exponential growth phase
how to estimate number of bacteria in colony
- assume each colony is made from one bacterium
- multiply number of colonies by dilution factor
disadvantages of immobilised enzymes
- immobilising may reduce activity rate
- higher initial costs
- more technical issues with bioreactor
advantages of immobilised enzymes over microorganisms
- less wasteful as no biomass is made, only product
- more efficient as isolated enzymes can be more concentrated than when in microorganism
- more specific so no wasteful side reactions occur
- maximise efficiency by using conditions optimum for the enzyme and not whole microorganism
- less purification as microorganisms produce variety of products
how is it possible to produce many clones from one original parent plant
- many explants taken from original plant
- calluses subdivided
- plantlets can be subdivided
how to ensure results are valid in experiment where you count number of bacteria
- use spreader to spread bacteria on agar, do not swirl plate as it may not be even and counting colonies will be more difficult
- label petri dish as soon as inoculated so dishes are not confused
- place petri dish upside down as this prevents agar drying out which would reduce growth
