Cloning & Biotechnology Flashcards
What is an immobilised enzyme?
an enzyme attached to an inert, insoluble material.
What are 4 methods of enzyme immobilisation?
- Adsorption
- Covalent bonding
- Entrapment
- Encapsulation
What is vegetative propagation?
the production of plant clones from non-reproductive tissues (e.g: roots, leaves and stems).
How do you produce a plant clone from a cutting?
1) use a scalpel to make a cut between 5cm and 10cm long, from the end of a stem of your parent plant.
2) remove the leaves from the lower end of your cutting leaving just one at this tip.
3) dip the lower end in rooting powder, which contains hormones that induce root formation.
4) plant your cutting in a pot containing a suitable growth medium (e.g: well-drained compost).
5) provide a warm and moist environment (i.e: cover with a plastic bag).
6) once the cutting has formed its own roots and is strong enough, you can plant it elsewhere.
How do you artificially clone a plant using tissue culture?
1) cells are taken from the original plant’s stem and root tips (as they can differentiate into an cell type).
2) sterilise the cells to prevent microbe competition for plant nutrients, which decrease growth rate.
3) place the cells in a culture medium containing plant nutrients and growth hormones.
4) once cells have divided and grown into a small plant they’re taken out of the medium and planted in soil.
What is micropropagation?
when tissue culture is used to produce lots of clones plants very quickly.
What are the arguments for artificial plant cloning?
+ desirable genetic characteristics are passed on (doesn’t always happen when reproduce sexually).
+ reproduce plants in any season.
+ less space needed by tissue culture (compared to conventional methods).
+ produce lots of plants quickly (compared to seeds).
What are the arguments against artificial cloning of plants?
-undesirable genetic characteristics passed on.
-no genetic variation, so single disease could kill.
-high production cost due to high energy use, so not suitable on a small scale.
-contamination by microorganisms can be disastrous, resulting in complete plant loss.
Describe the process of artificial embryo twinning.
1) egg cell is extracted and fertilised in a Petri dish.
2) fertilised egg is left to divide, forming an embryo in vitro (outside living organism).
3) individual cells from the embryo are separated and put into a separate petri dish, left to divide and develop into an embryo.
4) embryos are implanted in surrogate mother.
5) develop and are born, to produce genetically identical offspring.
Describe the process of somatic cell nuclear transfer.
1) somatic cell is taken from sheep A, keeping the extracted nucleus.
2) an egg cell is taken from sheep B, and is enucleated.
3) sheep A’s nucleus is inserted in to sheep B’s enucleated egg cell.
4) use electrofusion to fuse together and stimulate to divide, producing an embryo.
5) implant the embryo in the surrogate, sheep C. The lamb born is a clone of sheep A.
How do microorganisms help to brew beer?
- yeast is added to grain.
- it respires anaerobically using glucose from the grain.
- this produces ethanol and CO2. (via fermentation).
How do microorganisms help when baking?
- yeast makes bread rise.
- CO2 produced from fermentation of sugars.
How do microorganisms help to make cheese?
- rennet (traditionally extracted from calves’ stomachs, but now from GM yeast cells) contains an enzyme, chymosin, which clots milk.
- lactic acid bacteria is made, which converts lactose in milk into lactic acid which makes it turn sour and helps solidify it.
- blue cheese involves adding fungi.
How do microorganisms help to produce youghurt?
- uses lactic acid bacteria to clot milk and thicken it.
- flavours and colours are added.
How do microorganisms help to produce penicillin?
- in times of stress, fungi produce the antibiotic, to prevent bacteria from growing and competing for resources.
- it’s grown under stress in industrial fermenters.
