20 terms


Plasmids are important in biotechnology because they are
a. a vehicle for the insertion of foreign genes into bacteria.
If you discovered a bacterial cell that contained no restriction enzymes, which of the following would you expect to happen?
D) The cell would be easily infected and lysed by bacteriophages.
Which enzyme was used to produce the molecule in the figure below?
C) a restriction enzyme
Assume that you are trying to insert a gene into a plasmid. Someone gives you a preparation of genomic DNA that has been cut with restriction enzyme X. The gene you wish to insert has sites on both ends for cutting by restriction enzyme Y. You have a plasmid with a single site for Y, but not for X. Your strategy should be to
C) cut the DNA again with restriction enzyme Y and insert these fragments into the plasmid cut with the same enzyme.
What is the enzymatic function of restriction enzymes?
D) to cleave nucleic acids at specific sites
How does a bacterial cell protect its own DNA from restriction enzymes?
A) adding methyl groups to adenines and cytosines
What is a cloning vector?
A) an agent, such as a plasmid, used to transfer DNA from an in vitro solution into a living cell
What are the typical characteristics of a cloning vector?
D) Both B and C are correct.
What is the most logical sequence of steps for splicing foreign DNA into a plasmid and inserting the plasmid into a bacterium?
B) III, II, IV, V, I
Bacteria containing recombinant plasmids are often identified by which process?
C) exposing the bacteria to an antibiotic that kills the cells lacking the plasmid
Bacteria that contain the plasmid, but without the eukaryotic gene, would grow
D) in all four types of broth.
Bacteria containing a plasmid into which the eukaryotic gene has integrated would grow in
E) the ampicillin broth and the nutrient broth.
Bacteria that do not take up any plasmids would grow on which media?
A) the nutrient broth only
The principal problem with inserting an unmodified mammalian gene into a bacterial plasmid, and then getting that gene expressed in bacteria, is that
C) bacteria cannot remove eukaryotic introns.
A gene that contains introns can be made shorter (but remain functional) for genetic engineering purposes by using
C) reverse transcriptase to reconstruct the gene from its mRNA.
Yeast cells are frequently used as hosts for cloning because
D) they are eukaryotic cells
The DNA fragments making up a genomic library are generally contained in
A) recombinant plasmids of bacteria.
A eukaryotic protein can be made in bacteria by inserting the gene encoding the protein into a(n)
b. expression vector.
How does a genomic library differ from a cDNA library?
C) A genomic library can be made using a restriction enzyme and DNA ligase only, whereas a cDNA library requires both of these as well as reverse transcriptase and DNA polymerase.
The polymerase chain reaction is important because it allows us to
d. make many copies of a targeted segment of DNA.