Recombinant DNA technology

Question 1

What is recombinant DNA technology?

Answer 1

the process by which genes are manipulated, altered, or transferred from organism to organism

Question 2

What characteristic of the genetic code allows recombinant DNA technology to work?

Answer 2

universal

Question 3

What is recombinant DNA?

Answer 3

DNA from two different sources that has been joined together

Question 4

What is a transgenic organism?

Answer 4

has recombinant DNA

Question 5

What are three ways of getting a fragment of DNA?

Answer 5

-convert mRNA into cDNA using reverse transcriptase
-cut gene from DNA using restriction endonuclease
-creating the gene in a “gene machine”

Question 6

How can you amplify DNA?

Answer 6

using PCR

Question 7

What are the two outcomes of using restriction enzymes?

Answer 7

-some cut straight across both strands forming blunt ends
-most make a staggered cut in the two chains, forming sticky ends

Question 8

When can you use the “gene machine”?

Answer 8

when you know the primary structure of a protein

Question 9

How does the “gene machine” work?

Answer 9

-amino acid sequence is entered into a computer
-the triplet code for each amino acid is known so the DNA sequence that will produce that protein is worked out
-the computer then controls the machine and the required DNA sequence is made

Question 10

What is the promoter region?

Answer 10

it is attached to the DNA near a gene, is a binding site for RNA polymerase to start transcription and make a protein

Question 11

What is the terminator region?

Answer 11

is added to the other end of the fragment to stop transcription by releasing RNA polymerase

Question 12

What are 3 ways of transferring a vector to a cell?

Answer 12

-heat shock
-electroporation
-viruses

Question 13

What are two ways of cloning DNA fragments?

Answer 13

-in vivo: transferring fragments to a vector
-in vitro: using PCR

Question 14

What does PCR stand for?

Answer 14

polymerase chain reactions

Question 15

Why are sticky ends important?

Answer 15

-when the same restriction endonuclease is used to cut DNA, all the ends of the fragments will be complementary to each other
-when two complementary sticky ends join up, DNA ligase can be used to join the sugar-phosphate backbone

Question 16

What is used to transport DNA to the host cell?

Answer 16

a vector, like a plasmid, that often contains the gene for antibiotic resistance

Question 17

When will the sticky ends be complementary?

Answer 17

when the restriction endonuclease used to cut the plasmid is the same as that which is used to cut the DNA into fragments

Question 18

What does in vivo and in vitro mean?

Answer 18

in vivo = in the womb
in vitro = in glass/test tube/lab

Question 19

What is complementary DNA?

Answer 19

DNA that is made from RNA in a process that is the reverse of normal transcription

Question 20

What are restriction endonucleases?

Answer 20

enzymes used to cut DNA molecules

Question 21

What are reverse transcriptases?

Answer 21

enzymes involved in copying an mRNA code into a DNA molecule

Question 22

What are sticky ends?

Answer 22

ends of DNA fragments that have been cut with a restriction enzyme - can them be joined to a complementary cut piece of DNA

Question 23

Name the 5 stages of DNA technology

Answer 23

-isolation
-insertion
-transformation
-identification
-growth/cloning

Question 24

Explain how a piece of DNA could be isolated

Answer 24

-removes the DNA from its source
-such as adding a detergent, breaking down the cell membranes and freeing the DNA
-then digestive enzymes can be used to separate the specific gene wanted

Question 25

How are blunt ends formed?

Answer 25

when restriction endonucleases act straight across both strands

Question 26

What knowledge is required to use the gene machine?

Answer 26

the primary structure of a protein

Question 27

Explain the process of making protein using a gene machine

Answer 27

-amino acid sequence is entered into a computer
-the triplet code for each amino acid is known so the DNA sequence that will produce the protein is worked out
-the computer then controls the machine and the required DNA sequence will be made