Cloning + Biotechnology Flashcards
Asexual reproduction
Is a form of cloning and it results in offspring produced by mitosis, clones aes usually genetically identical to both the parent organism
Natural cloning in plants
Occurs in many species of flowering plant
A structure forms which develops in a fully different plant which is genetically identcial to the parent
Occurs in: bramley apples, bulbs, runners ( strawberrys), rhizomes ( grass), stem tubers ( potato)
Micropropagation definition
Process of making large numbers of geneticslly identcia, offspring from a single parent using tissue culture techniques, produces desirable plants
When is micropropagation used
When plants:
dont regulally produce seeds
Dont respond to natural cloning
Are very rare
Have been selectively bred with difficulty
Is required to be pathogen free by growers
Aseptic techniques
Autoclave- high pressure = higher boiling point of water (140 degrees)
Bunsen - heats air up and away from test tube
P.P.E - personal protective equipment
Disinfect surface
Laminar flow - room has high pressure
Clean forceps
Advantages for micropropagation
- Allows for production of large numbers of plants with known genetic makeup which yeilds good crops
- culturing meristem tissue produces disease free plants
- provides a way to grow plants which are naturally relatviely infertile
- provides a way of reliably increasing the numbers of rare or endangered species
- can produce plants which are seedless + sterile therfore meet consumers tastes and needs
- possible to produce viable numbers of plants after genetic modificstion of plant cells
Arguments against micropropagation
Produces a monoculture, all organisms are susceptible to the same disease
Expensive and requires skilled workers
If source material is infectes with a virus all the clones will have that virus
Large number of plants aes lost during the process
Explants + plantlets are vunerable to disease during the production process
Basic principles of micropropagation and tissue culture
- Take a small sample of tissue from the plant you want to clone - meristem tissue from shoot tips and axial buds is often dissected out into sterile to avoid contamination by fungi or virus
- sample is sterilised by immersing it in sterilising agents such as ethanol or bleach. The material removed from the plant is called explant
- explant is placed in a sterile culture medium containing a balance of hormones which stiumlate mitosis. The cells proliferate forming a mass of identical cells known as a callus
- the callus is divided up and individual cells or clumps from the callus are transferred to a new culture medium containing a different mixutre of hormones and nutrients whcih stiumlate the development of geneticallt identical plantlets
- plantlets are plotted imto the compost where they grow into small plants
stages of artificial twinning
- cow with desirable traits is treated with hormones so she super ovulates
- ova are fertilised ( either naturally or artificially)
- whilst the cells are still totipotent they are harvested and split to produce several smaller embryos capable of growing into a full-term calf
- embryos are grown in lab for a few days then implanted into a surrogate mother due to lower risk
- embryos develop in foetuses and are born naturally
process of somatic cell nuclear transfer
- the nucleus is removed from a somatic cell of an adult animal
- the nucleus is removed from a mature ovum harvested from a different female animal of the same species ( it is enucleated)
- the nucleus from the adult somatic cell is placed into the enucleated ovum and given a mild electrical shock so it fuses and begins to divide. in some cases nucleus from the adult cell is not removed it is simply placed next to the enucleated ovum and the 2 cells fuse and begin to divide
- the embryo that develops is transferred into the uterus of a third animal where it develops into a term
- new animal is a clone from the original, but will have the mitochondrial DNA from the egg cell
arguments for animal cloning
- enables high yielding farm animals to produce many more offspring than normal reproduction
- somatic cell nuclear transfer enables GM embryos to be replicated giving many GM embryos from one procedure
- allows specific animals such as pets or top class racing horses to be cloned
- endangered or rare species could be reproduced
arguments against animal cloning
- somatic cell nuclear transfer is a very inefficient process, in most animals it takes many eggs to produce a single cloned offspring
- many cloned animal embryos fail to develop and miscarry or produce malformed offspring
many animals produced by cloning have shortened life spans
what is biotechnology
involves applying biological organisms or enzymes to the synthesis, breakdown, or transformation of materials in the service of people
genetically modifying microorganism synthesising drugs such as insulin and antibiotics
what is bioremediation
use of biological systems to remove soil and water pollutant
This can be through the use of natural organisms or genetically modified organisms which can break down or accumulate contaminants which they would not naturally encounter
microorganisms involved in baking
yeast- is mixed with sugar and water to respire aerobically.
carbon dioxide produced makes bread rise
microorganisms involved in Brewing
yeast - respires anaerobically yo produce ethanol
traditional yeast ferment at 20-28 degrees, GM yeast ferment at lower temps therefore are cheaper and sink at the end of the process to produce clear beer
microorganisms involved in cheese making
bacteria - feed on lactose in milk, changing the texture and taste, and inhibiting the growth of bacteria which can make milk go off
microorganisms involved in yoghurt making
bacteria- produce extracellular polymers that give yoghurt its smooth thick texture
Use of natural cloning in horticulture
Farmers take cuttings of plants and re planting them increases numbers cheaply, these new plants all have the same genetic characteristics as their parents
Rooting hormones are often used to promote root growth
A - taking cuttings from good stock the offspring will be identical
D - disease susceptibility
Natural clones in animal species
Cloning in invertebrates - some animals can regenerate entries animals from fragments of the original if they are damaged
In insects of females can produce offspring without mating
cloning in vertebrates - embryos splitting formation of monozygotic/ identical twins
Why microorganisms are used
No welfare issues to consider
Enormous range of microorganisms capable of carrying out many different chemical synthesis or degradations
Genetic engineering allows us to artificially manipulate microorganisms to carry out synthesis reaction that they would not normally, e.g insulin
Microorganisms have a very short life cycle and rapid growth rate, given the right conditions huge quantities of microorganisms can be produced
Nutritional requires are very simple and cheap
Conditional requirements are cheap as they produced their own catalysts
Advantages of using microorganisms to produce human food
Reproduce fast and produce protein faster than animals and plants
have high profile content with little fat
Can use a wide variety of waste materials including human and animal waste, reducing cost
Can be genetically modified to produce the protein required
Production of microorganisms is not dependant on weather/breeding cycles - it takes place constantly and can be easily increased or decreased
No welfare issues
Can be made to taste like anything
Disadvantages of using microorganisms to produce human food
Some microorganisms can also produce toxins if the conditions are not maintained at the optimum
The microorganisms have to be separated from the nutrient broth and processed to make the food
Need sterile, carefully controlled conditions adding to the cost
Often involve FM organisms and many people have concerns about eating GM food
The protein has to be purified to ensure it contains no toxin or containments
Many people dislike the thought of eating microorganisms grown on waste
Has little natural flavour, needs additives
Stages of Producing penicillin and factors of production medium
Produce in semi continuous batch process, 1st stage fungus grows, 2nd it produces penicillin, finally the drug is extracted from the medium and purified
- uses relatively small fermenters to keep oxygen levels high
- mixture is continuously stirred
- there is a nutrient rich medium
- growth medium contains a buffer to maintain PH around 6.5
- Bioreactors are maintained at about 25-27 degrees
Limiting factors preventing exponential growth of bacteria
Nutrients , oxygen levels , temperature , build up of waste , change in pH
methods of enzyme immobilisation
Surface immobilisation - adsorption to inorganic carriers
Surface immobilisation - covalent or ionic binding to inorganic carriers
Entrapment in matrix - e,g polysaccharides, gelatin
Entrapment - membrane entrapment in microcapsules or behind a semi permeable membrane
Advantage of using immobilised enzymes
- Can be reused - cheaper
- Easily separated from the reactants and products of the reaction they are catalysing so reduced downstream process - cheaper
- More reliable - higher degree of control over the process, keeps micro environment stable
- Greater temperature tolerance - work at optimum over greater range of temp
- Ease of manipulation - e,g immobilised glucose isomerise can be used continuously for over 1000 hours at 60-65 degrees, ability to keep bioreactors running for long periods of time reduces cost
Disadvantages of using immobilised enzymes
May reduce efficacy by immobilising
High initial cost to immobilise the enzymes
High initial costs of bioreactor
More technical issues - more things can go wrong
Advantages of batch culture
Easy setup
Once fermenter is cleaned it is ready to go again
If contaminated only 1 batch is ruined
In continuous culture the cells can sometimes clump together causing a block
Advantages of continuous culture
Less downstream time
Can just be left to work, less manual labour
Metabolite definition
The Intermediate and products of metabolism
Primary metabolite - directly involved in normal growth, development + reproduction
Secondary metabolite - is not directly involved in those ^ processes but usually has an important ecological function, often made outside of the main growth phase
Good source of nitrogen for batch culture and its use
Ammonia
Nitrogen is used to produce molecules containing nitrogen e.g amino acids
Use of glucose isomerase
conversion of glucose -> fructose
Fructose is sweeter so is cheaper to use and less caloric for the same sweetness
Use of immobilised penicillin acylase
- make semi-synthetic penicillins from naturally produced penicillin
- some bacteria are resistant to natural but are still vulnerable to semi synthetic penicillin
Use of immobilised lactase
Some people are lactose intolerant
Used to produce lactose free milk
Hydrolyses lactose -> glucose + galactose
Use of immobilised amino acylase
Produces pure samples of l-amino acids used in the production of pharmaceuticals
Use of immobilised glucoamylase
Used to compete the breakdown of starch to glucose syrup
Break down starch into short chain polymers called dextrin, final breakdown of dextrin -> glucose done by glucoamylase
Definition of a callus
A callus is a group of undifferentiated cells created in an artificial medium after the meristematic (explant) was removed from an apical or lateral bud of a plant
Benefits of cloning to pass on advantageous alleles rather than breeding
All offspring will inherit the gene
Avoid mating risks
May be obtained quicker
Disadvantages No genetic variability = susceptible to disease Shortened life spans Cloning success rate is very poor Very expensive
Disadvantages of using yeast instead of oil
Potentially slower rate of reaction
Extensive down streaming process
Killed by toxic product ethanol
Sterile conditions needed
