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Question 1

What does recombinant DNA technology involve?

Answer 1

the transfer of DNA fragments from one organism to another.

Question 2

What is the name of the sections of DNA that are transferred?

Answer 2

DNA fragments

Question 3

3 main methods to produce DNA fragments:

Answer 3

1. Using Reverse transcriptase to convert mRNA to cDNA
2. Using restriction enzymes to cut a fragment containing the desired gene
3. Creating the gene in a ‘gene machine’

Question 4

Producing DNA fragments using restriction enzymes, stages:

Answer 4

1. DNA containing target gene is mixed with the restriction endonucleases
2. Restriction endonucleases bind to the specific recognition sequences on either side of the target gene.
3. Target gene is cut out of DNA

Question 5

Producing DNA fragments using gene machines

Answer 5

1. sequence obtained from database
2. nucleotides added in correct order (to synthesise correct base sequence)
3. Protecting groups added (to ensure correct N & no side branches)

Question 6

Fragments of DNA can be amplified via either _________ or _________ techniques

Answer 6

in vivo (inside), in vitro (outside)

Question 7

In vivo- stages

Answer 7

1. vector DNA cut open by restriction endonucleases, leaving two short single-stranded sections (sticky ends)
2. Addition of promoter & terminator regions to fragments of DNA?
3. Inserting DNA fragments into vectors using endonucleases & ligases
4. transfer of recombinant DNA to host cell via heat shock
5. inserting of marker genes to detect GM cells

Question 8

how does the insertion of marker genes help detect GM cells

Answer 8

when cells are placed on an agar plate with antibiotics only the cells which have taken up recombinant DNA will survive

Question 9

In vitro method to amplify DNA- PCR

Answer 9

1. DNA fragments mixed with: primers, DNA polymerase & free-floating nucleotides
2. Mixture heated to 95 degrees- breaking H bonds between DNA strands separating them into 2
3. Mixture cooled to 65 degrees- this caused primer? to ANNEAL to 2 separate strands
4. mixture heated to 72 degrees, (optimum temp for DNA polymerase)
5. DNA polymerase creates new strands using separated strands as templates & adding free-floating complementary nucleotides
6. Primers allow nucleotides to bind to one another & produce a strand of DNA.
7. Process repeated

Question 10

Uses of Recombinant DNA technology

Answer 10

• GM crops
• GM livestock
• Increased nutritional value
• Treating diseases
• Industry

Question 11

Disadvantages of recombinant DNA technology

Answer 11

• spread of genes could be harmful
• ## unforeseen impacts (on gene function/ on variation & biodiversity)