Selective breeding and genetic engineering Flashcards
(8 cards)
What is selective breeding
Where humans a… select the plant or a… that are going to b… so that the g… for particular c… remain in the p…
Where humans artificially select the plant or animals that are going to breed so that the genes for particular characteristics remain in the population
How does selective breeding work
-from your e… stock you s… the ones with the desired c…
-you then b… them with eachother and select the best o… and b… them together
-continue this p… over several g… and the desirable t… will become more p…
-eventually all the o… will have this c…
-from your existing stock you select the ones with the desired characteristics
-you then breed them with eachother and select the best offspring and breed them together
-continue this process over several generations and the desirable trait will become more prominent
-eventually all the offspring will have this characteristic
What are the disadvantages of selective breeding
-it r… the g… pool
-can cause h… problems
-more likely chance of i… harmful d…
-if a new d… appears it can w… out a whole p…
-it reduces the gene pool
-can cause health problems
-more likely chance of inheriting harmful defects
-if a new disease appears it can wipe out a whole population
What is inbreeding
Where the animals or plants that are the best are repeatedly bred which are all closely related
What is genetic engineering
Is to transfer a g… responsible for a desired c… from one organisms g… to another o… so that it will also have the d… characteristics
Is to transfer a gene responsible for a desired characteristic from one organisms genome to another organism so that it will also have the desired characteristics
How does genetic engineering work
-a u… gene is i… (cut) from one organisms g… using e… and is inserted into a v…
-the vector is usually a v… or p…
-when the vector is introduced to the t… organism the useful g… is inserted into its c…
-a useful gene is isolated (cut) from one organisms genome using enzymes and is inserted into a vector
-the vector is usually a virus or plasmid
-when the vector is introduced to the target organism the useful gene is inserted into its cells
Examples when genetic engineering is used
-b… have been genetically m… to produce human i… to treat d…
-genetically m… crops have made them r… to d… and w… killers
-sheep have been genetically e… to produce s… in their m… that treat h… diseases
-bacteria have been genetically modified to produce human insulin to treat diabetes
-genetically modified crops have made them resistant to disease and weed killers
-sheep have been genetically engineered to produce substances in their milk that treat human diseases
Pros and cons of genetically modified crops
Pros:
-can increase the y…, making more f…
-can increase the n… in food
—>useful for … countries
Cons:
-reduces b… as it will affect the number of wild f… and i… around the crops
-not everyone believes they are s…, and feel we do not know the full e… on human h…
-believe that t… genes may get out into the n… environment
—>eg weeds pickup h… resistance
Pros:
-can increase the yield, making more food
-can increase the nutrients in food
—>useful for developing countries
Cons:
-reduces biodiversity as it will affect the numb of wild flowers and insects around the crops
-not everyone believes they are safe, and feel we do not know the full effect on human health
-believe that transplanted genes may get out into the natural environment
—>eg weeds pickup herbicide resistance
