GM Products + Cloning

Question 1

how is insulin manufactured in a fermenter?

Answer 1

• the transgenic bacteria is placed into a fermenter in order to increase in number
• this is sterilised prior to use - the nutrient medium and air entering the system is also sterilised to prevent the growth of pathogens or competing microorganisms
• if the bacteria have enough nutrients and are kept at their optimum conditions they will begin to produce human insulin

Question 2

what steps need to be taken in order to make the insulin in the fermenter?

Answer 2

• providing oxygen via the air line
• stirring the mixture to prevent clumping and a shortage of nutrients
• monitoring the temperature and cooling the fermenter if needed
• adding more nutrient medium

the insulin is secreted by the bacteria - it is then collected from the fermenter, purified and distributed

Question 3

what are the two main stages of genetically modifying plants?

Answer 3

• introducing the new gene or genes into plant cells
• producing whole plants from just a few cells (tissue culture)

Question 4

which bacterium is used to genetically modify plants?

Answer 4

agrobacterium tumefaciens - because it regularly inserts plasmids into plant cells, adding genes to the plant chromosomes

Question 5

what kind of different traits can be added to plants?

Answer 5

• higher yield
• ability to produce extra nutrients
• resistance to extremes in weather
• resistance to pests
• resistance to disease/pathogens

Question 6

what are advantages of genetically modifying plants?

Answer 6

• more precise method than selective breeding
• high crop yield/better food quality
• less pesticide/herbicide used to less pollution
• disease resistant/pest resistant/herbicide resistant

Question 7

what are the disadvantages of genetically modified plants?

Answer 7

• not accepted by the public
• long term affects unknown
• may affect food chains or environment
• reduces variation

Question 8

what is artificial propagation?

Answer 8

when you propagate (produce) many plants by taking cuttings from leaves, roots or stems

Question 9

what is another method of producing much larger numbers of genetically identical plants?

Answer 9

tissue culture or micro propagation - this is useful for plants that are difficult to propagate by seeds or cuttings - whole plants are grown from individual cells for from small parts of plant tissue

Question 10

what is the process of micro-propagation?

Answer 10

1. a small section (explant) is cut from the desired plant, it is sterilised and placed onto a nutrient gel, where it grows into a small ball of cells (callus)
2. small groups of cells are then taken from the callus and enter further stages of multiplication, rooting and acclimatizing and then transferring the plants into new soil - plant hormones are used to stimulate shoot and root growth, these small bundles of cells grow into individual cloned plants

if the plant has desirable features such as a high resistance to a specific pest, then the young plants will have this feature too - micro-propagation can also be used to increase the number of a genetically modified plant

Question 11

what are gene banks?

Answer 11

where seeds of all different varieties are kept, in case breeders may want to use them in years to come

Question 12

how are animals cloned?

Answer 12

• the DNA is extracted as a whole nucleus
• an electric shock is used to fuse the nucleus and empty (enucleated) egg cell, this also stimulates mitosis

Question 13

what can cloning animals also be useful for?

Answer 13

to save species that are close to extinction

Question 14

what is the research being done to clone human body parts for transplant surgery?

Answer 14

• pigs could be genetically modified to have human antigens (recognition proteins) on their cell membranes
• this could allow pig organs to be transplanted into humans as it would reduce the immune response against the organ and risk of rejection
• another possibly would be to genetically engineer goats or similar animals to produce human proteins, for example antibodies, in their milk
• the genetically modified pigs to be cloned to increase the population
• the proteins could be collected from the milk and used to treat patients with weak immune systems

Question 15

what are complications of genetically cloning pigs?

Answer 15

xenotransplantation (transplants between different species) could lead to viruses being transferred between species