8.2 Gene Technology

Question 1

explain how strands of DNA are separated during the PCR

Answer 1

by heating and hydrolysing hydrogen bonds

Question 2

describe the polymerase chain reaction (6)

Answer 2

heat to 95 DNA and break hydrogen bonds to seperate strands
add primers and DNA nucleotides
cool to allow binding of primers
add DNA polymerase to join nucleotides to DNA strand
repeat many times

Question 3

describe how genetic fingerprinting is carried out and explain how it can be used to identify a person.

Answer 3

extract DNA and cut it using restriction endonucleases
seperate DNA fragments according to length using gel electrophoresis
DNA is made single standed
transfer to membrane and apply radioactive probe to VNTRs to allow position of fragments to be visualised as bands the pattern formed is unique to every individual

Question 4

what is recombinant DNA

Answer 4

DNA which contains genes/nucleotides from two different species or type of organism

Question 5

role of reverse transcriptase

Answer 5

produces cDNA using mRNA