3.8.4 - Gene Technologies Flashcards
(10 cards)
1
Q
describe and explain how the polymerase chain reaction (PCR) is used to amplify a DNA fragment
A
- requires DNA fragment, DNA polymerase, nucleotides and primers
- heat to 95°C to break hydrogen bonds and separate strands
- reduce temperature to 55°C so primers bind to DNA/strands
- increase temperature to 72°C, DNA polymerase joins nucleotides
- repeat method
2
Q
role of restriction enzymes in inserting DNA fragments into plasmids
A
- restriction endonuclease cuts plasmid
- produces ‘sticky ends’
3
Q
role of ligase enzyme in inserting DNA fragments into plasmids
A
- ligase joins gene/DNA to plasmid
- joins ‘sticky ends’
4
Q
role of reverse transcriptase in RT-PCR
A
- produces cDNA using mRNA
5
Q
role of DNA polymerase in RT-PCR
A
- joins nucleotides to produce (complementary strand/s of) DNA
6
Q
what is a DNA probe?
A
- short, single strand of DNA
- bases complementary (with DNA/allele/gene)
7
Q
describe how DNA is broken down into smaller fragments
A
- restriction endonuclease/enzyme
- (cuts DNA at specific) base sequence
- (breaks) phosphodiester bonds
- (cuts DNA) at recognition/restriction site
8
Q
explain why the DNA on the nylon membrane is treated to form single strands
A
- (so DNA) probe binds/attaches/anneals
9
Q
what is meant by a non-coding base sequence?
A
- does not code for amino acid/tRNA/rRNA
10
Q
name the method used to clone DNA in vitro
A
- polymerase chain reaction (PCR)
