DNA technology in agriculture

Question 1

what is selective breeding?

Answer 1

organisms with certain phenotypic characteristics are chosen for breeding stock at each generation

Question 2

what does culled mean?

Answer 2

individuals with unwanted phenotypes are prevented from breeding

Question 3

what is hybridisation?

Answer 3

the crossing of individuals from different varieties to produce a predictable phenotype in the F1 generation with dominant characteristics of both breeds.

Question 4

what are transgenic crops?

Answer 4

contains DNA from two different species

Question 5

what are cisgenic crops?

Answer 5

artificially transfer of genes between individuals of the same species

Question 6

what are the stages of transforming bacteria?

Answer 6

1. mRNA of desired gene is harvested from a eukaryotic cell and complementary DNA is manufactured using enzyme - reverse transcriptase
2. manufactured gene for protein is spliced into a plasmid using ligase
3. recombinant plasmid created

Question 7

what is the purpose of the gene for antibiotic resistance in the plasmid?

Answer 7

for selection of the bacteria containing the recombinant plasmid by growing it on a medium containing the antibiotic. creates a pure culture

Question 8

what is bovine somatotrophin? (BST)

Answer 8

example of the use of genetic transformation of bacteria in agriculture by E.coli
increases milk production as it prevents mammary cell death an increases duration of lactation

Question 9

which microorganism is responsible for the production of BST?

Answer 9

E.coli

Question 10

what is a recombinant plasmid?

Answer 10

a plasmid containing foreign DNA

Question 11

what is a cloning vector?

Answer 11

transfers foreign DNA into a bacterial cell to replicate there

Question 12

sometimes proteins produced from genetically modified microorganisms do not function properly, why?

Answer 12

many proteins require processing to make them function properly, for example by addition of a carbohydrate group.
these proteins can only be obtained in their mature, fully functional form when produced by eukaryotic cells.

Question 13

where is the Ti (tumour-inducing) plasmid?

Answer 13

in Agrobacterium

Question 14

in normal circumstances what is the plasmid’s use?

Answer 14

to cause a tumour or gall to form to increase the habitat for the bacterium

Question 15

what is an ori sequence?

Answer 15

important sequence that allows it to be replicated in a plasmid

Question 16

what are protoplasts?

Answer 16

plant cell that’s cell wall has been digested with cellulase

Question 17

give an example of a transgenic crop

Answer 17

flavr savr tomato - fruit stays firmer for longer allows producers a greater period of time for transportation, harvesting without bruising as well