cloning and biotechnology Flashcards
what regions of a plant is capable of vegetative reproduction
root and shoot tips
auxiliary buds (where leaves and stems meet)
vascular cambium (between xylem and phloem)
outline the steps of taking a cutting
- using a scalpel, take a cutting of a healthy stem between nodes from parent plant at a slant
- remove leaves from lower end of cutting
- dip the lower end in rooting powder
- place plant in pot containing suitable growth medium
- provide cutting with warm and moist environment by covering with a plastic bag
- when roots have formed, place in soil.
outline the steps of tissue culture
- cells from stem and root tip are taken from the original plant
- cells are sterilised with dilute bleach to kill any microorganisms.
- cells are placed on a culture medium
- should be carried out using aseptic conditions
- cells are left to divide to produce a mass of undifferentiated cells called a callus
- the mass is subdivided to produce many plants quickly, they are left to divide and grow then placed in soil.
what are some advantages of cloning plants
can close plants that don’t easily reproduce or are endangered.
can grow plants with desirable characteristics which are always passed on
can grow plants in any season
less space is required compared to conventional growth methods
time efficient
what are some disadvantages of cloning plants
no genetic variability so single disease can kill entire crop
contamination by microorganisms can be disastrous and result in complete loss of crop
outline the process of artificial embryo twinning
- an egg cell is extracted from the animal and fertilised in petri dish
- fertilised egg is left to divide forming an embryo in vitro
- individual cells from embryo are separated and each is placed into a separate petri dish. an embryo forms in each dish
- embryo is then implanted into a surrogate mother where it continues to develop
outline the process of somatic cell nuclear transfer
- from sheep A a somatic cell is taken and the nucleus is extracted and kept.
- an immature egg cell is taken from sheep B and its nucleus is removed to form an enucleated cell
- nucleus from sheep A is inserted into the enucleated cell where they fuse together and stimulated to divide eg. by electrofusion
this produces an embryo - the embryo is implanted into a surrogate mother
what are some advantages of animal cloning
can test drugs on cloned animals as they are genetically identical therefore genetic variables are controlled.
can be used to increase the number of animals with desirable characteristics
an animal that has been genetically modified to produce a beneficial substance in it’s milk could be cloned.
clones can be used to save endangered animals from extinction
what are some disadvantages of animal cloning
animal cloning has low success rates and is time consuming and expensive
no genetic variability therefore all clones are susceptible to disease
clones may have shorter lifespans and more health problems for example dolly the sheep had to be put down at 6 years due to severe arthritis
what is biotechnology
the industrial use of living organisms to produce food, drugs ect.
why are micro-organisms often used in biotechnology
their ideal growth conditions can be easily created
short life cycle so grow rapidly under right conditions
can grow on inexpensive materials eg. waste
can be grown any time of the year
what microorganism is used to make beer
yeast
what microorgamism is used in cheese making
bacteria
what micro-organism is used to make yoghurt
bacteria
what is bioremediation
process of using living organisms to remove pollutants such as oil and pesticides from contaminated sites
what are primary metabolites
metabolites needed for growth of microorganisms during log/lag phase
what are secondary metabolites
not needed for growth of microbes
what is batch fermentation
where micro-organisms are grown in individual batches in a fermentation vessel. When one culture ends it is removed, the vessel is resteralised to avoid contamination. A different batch of microorganisms is then grown.
what is continous fermentation
where micro-organisms are continually grown in a fermentation vessel, without stopping. Nutrients is put in and waste products taken out at a constant rate
in pencillin production, which is more likely to be used, batch fermentation or continous
batch
which type of metabolites are harvested during continous fermentation
primary
which factors need to be controlled during fermentation
pH
temperature
oxygen supply
nutrient concentration
contamination
what is downstream processing
the purification of the product that has left the fermenter
which type of fermentation is there less downstream processing, why is this an advantage
continuous
means there is less time spent with the vessel off therefore product therefore more profit.
what phase of a standard growth curve, are secondary metabolites produced
stationary phase - when there is a limiting factor.
outline the lag phase of the standard growth curve
population size increases slowly
micro-organisms are adjusting to the environment eg. making enzymes
reproduction rate is low
out line the log (exponential) phase of the standard growth curve
population size is increasing very quickly.
conditions are at the most favourable for reproduction
number of micro-organisms doubles at regular intervals
outline the stationary phase of. the standard growth curve
population size stays level, birth rate = death rate.
micro-organisms die as lack of food and waste products build up
outline the decline phase of the standard growth curve
population size falls as death rate is greater than birth rate
food is very scarce, excess waste products at toxic level.
outline how u may set up culturing micro-organisms in a lab
- use a sterile innoculation loop to transfer some of the sample to the plate
- using a glass spreader, spread the sample gently across the whole surface of the agar.
- plate is incubated + left to grow
outline aseptic technique
- regularly disenfect work spaces
- work near a bunsen burner- creates an updraft so any micro-organisms in air should be drawn away from the culture
- steralise instruments before and after by dipping in ethanol and passing through a bunsen burner
- if using broth, briefly pass neck of broth container through flame after its opened and just before its closed
- minimise the time the agar plate is open foor, placing lid on as soon as possible
- steralise glasswear using an autoclave
- wear lab coat and gloves
what is the purpose of aseptic technique
used to avoid the contamination of unwanted organisms
what is an immobalised enzyme
enzyme which is attached/ trapped into an inert matrix/material which prevents them from being mixed with the products
what are the 4 main ways enzymes are immobalised
- entrapment - trapped in a silica gel matrix or cellulose fibres or can be trapped in a liquid eg. alginate beads - semi-permeable. (substrates and products must be small)
- enzymes are covelantly bonded to a surface or other enzymes using a cross linking agent - this forms chains. (more expensive less likely to mix with reaction mixture)
- adsorbtion - enzyme molecules are bound to a supporting surface by ionic links and hydrophobic interactions (could distort active site)
what are the advantages of using immobalised enzymes
enzymes can be washed and reused which reduces cost
product isn’t mixed with the enzymes so no money/time spent separating them
immobalised eznymes are more stable so less likely to denature at high temp/pH
what are the disadvantages of using immobalised enzymes
- extra equipment needed
- can be more expensive than isolated free enzymes
immobilisation can sometimes lead to a reduction in enzyme activity as can’t collide and interact with substrate as much
what are isolated enzymes
enzymes out of the cell either naturally secreted (Extracellular) or artificially extracted
