Recombinant DNA technology

Question 1

What is the purpose of recombinant DNA technology?

Answer 1

• allows genes to be manipulated and transferred from organism to organism
• allows us to understand how organisms work
• medical treatments

Question 2

What are the stages involved in the process of making a protein using the DNA technology of gene transfer and cloning?

Answer 2

• isolation of the desired gene
• insertion of DNA fragment into a vector
• transformation of DNA into host cell
• identification of host cells with gene markers
• growth/cloning of host cells

Question 3

How do you produce gene fragments?

Answer 3

• use reverse transcriptase to convert mRNA to cDNA
• use restriction enzymes
• a gene machine

Question 4

What is the process of reverse transcriptase to produce gene fragments?

Answer 4

1-a cell that has the desired gene is selected
2- the relevant mRNA extracted
3-reverse transcriptase then used to make DNA from mRNA
-this DNA is known as cDNA because it is made up of the nucleotides that are complementary to the mRNA
-to make the other strand of DNA, the enzyme DNA polymerase is used to build up the complementary nucleotides on the cDNA template
-this double strand of DNA is the required gene

Question 5

How are restriction enzymes used to produce DNA fragments?

Answer 5

• restriction enzymes cut up DNA at recognition sites
• some restriction enzymes leave a blunt end
• other restriction enzymes leave an uneven cut in which each strand of the DNA has exposed, unaired bases that are palindromes

Question 6

What are the advantages of using a gene machine?

Answer 6

• quick and accurate

- they have no intros, so can be transcribed and translated by prokaryotic cells

Question 7

How do you manufacture genes using a gene machine?

Answer 7

1, the amino acid sequence of the desired protein is determined
2,the mRNA codons are looked up and the complementary bases for the gene is fed into a computer
3-the sequence is checked for biosafety and biosecurity
4-the computer designs a series of oligonucleotides, which can be assembled into the desired gene
5-the oglionucleotides are assembles in an automated process to make a gene with no interns
6, the gene is replicated using the polymerase chain reaction

Question 8

How can recombinant DNA technology treat disease?

Answer 8

• a number of human diseases result from individuals being unable to produce for themselves various metabolic chemicals so the gene wanted could be extracted
• this chemical could be extracted from a human or animal donor and introduced into the patient
• this treatment is expensive and runs the risk of being rejected by the patient
• to prevent this genes and grown rather than transferred by recombinant DNA technology

Question 9

how then is it possible that the DNA of one organism is not only accepted by a different species but also functions normally when it is transferred?

Answer 9

-the genetic code is universal and can be transcribed and translated within the cells of the recipient so the proteins it codes for can be manufactured in the same way

Question 10

What is PCR?

Answer 10

1, denature: heat the reaction to break the hydrogen bonds causing the strands to separate (add primer)
2, Annealing: cool the reaction so the primers can bind to complementary exposed bases
3, Extension: Temperature is raises so Taq polymerase extends the primer to produce new strands of DNA
4, Repeat: cycle is repeated to produce more DNA