cloning and biotech🤖 Flashcards
(55 cards)
1
Q
explain relationship between sugar concentration falling and ethanol concentration increasing in a bacteria pop
A
- sugar converted to ethanal
- anaerobic respiration
- sugar undergoes glycolysis
- pyruvate forms ethanal
- NADH gives H to ethanal
- NAD regenerated
2
Q
why is ethanol considered a primary metabolite of yeast
A
produced during normal growth
3
Q
2 factors that may limit max size of yeast population
A
- sugar concentration falls too low
- pH falls too low
4
Q
methods of immobilising enzymes
A
- 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
5
Q
benefits of immobilised enzymes
A
- 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
6
Q
4 stages of bacterial growth are
A
- lag phase
- log phase
- stationary phase
- death phase
7
Q
what is a primary metabolite
A
- molecule made in or needed for normal growth
- eg glucose or ethanol
8
Q
2 factors in a fermenter to maximise bacteria growth
A
- maintain optimum temp
- increase O2
9
Q
define recombinant DNA
A
DNA combined from 2 sources
10
Q
outline process by which a goat may be cloned
A
- somatic nucleus fused with empty egg cell from another goat
- by electric shock
- this cell grown in vitro
- embryo split
- embryos put in surrogates
11
Q
what is ethanol used for in plant cloning
A
sterilising the plant tissue
12
Q
the tissue sample removed in plant cloning is called…?
A
the explant
13
Q
in plant cloning, what is the mass of cells produced called
A
callus
14
Q
differences between TLC and gel electrophoresis
A
- 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
15
Q
how to increase rate at which bacteria take up plasmids
A
electroporation
16
Q
in genetic engineering of e.coli why is a plasmid containing antibiotic resistance gene used
A
acts as marker gene to indicate which bacteria have taken up plasmid
17
Q
how to use PCR to compare e.coli growth rates on cancerous liver tissue and healthy tissue
A
- extract DNA from cancerous liver tissue and healthy tissue
- choose primers for e.coli and DNA
- compare rate of DNA amplification
18
Q
uses of dna profiling
A
- paternity
- forensics
- classification
19
Q
why are some regions of DNA described as non coding
A
- introns are non coding
- not present in mature mRNA
- not translated
- regulatory genes
20
Q
why do non coding regions of DNA show more variation
A
not selected against
21
Q
describe micro propagation
A
- 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
22
Q
disadvantage of micropropagation
A
- 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
23
Q
what is artificial embryo twinning
A
many identical embryos from one developing embryo
24
Q
disadvantage of animal cloning
A
no genetic variation
25
what is biotechnology
use of organisms in technology to make a useful product
26
what does aseptic mean
without microorganisms
27
list two aseptic techniques
- sterilising equipment
| - hand washing
28
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
29
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
30
what type of fermentation produces penicillin and why
batch
| -penicillin is a secondary metabolite and only produced at a later stage
31
which enzyme is used to make fructose syrup
glucose isomerase
32
advantages of continuous fermenter
- fermenter always in use
| - high yield
33
why is there a lag phase in growth
making proteins essential for growth takes some time
34
examples of natural plant clones
- bulbs eg daffodil
- runners eg strawberry
- rhizomes eg marram grass
- stem tubers eg potato
35
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
36
advantages of plant cloning
- faster than growing from seeds
| - guaranteed good quality plants
37
what is micropropagation
process of making a large number of genetically identical plants from a single parent plant using tissue culture techniques
38
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
39
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
40
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)
41
methods of animal cloning
- artificial embryo twinning
| - somatic cell nuclear transfer
42
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
43
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
44
advantages of artificial embryo twinning
-animals with desired traits can produce many more offspring than naturally
45
advantages of SCNT
- enables cloning of specific animals
| - endangered animals can be reproduced
46
disadvantages of SCNT
- inefficient process, takes many eggs to produce, many result in miscarriage
- shortened life spans
47
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
48
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
49
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
50
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
51
how to estimate number of bacteria in colony
- assume each colony is made from one bacterium
| - multiply number of colonies by dilution factor
52
disadvantages of immobilised enzymes
- immobilising may reduce activity rate
- higher initial costs
- more technical issues with bioreactor
53
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
54
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
55
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
