Mastering Microbiology #7
Synthetic nucleic acids are useful as
DNA probes, primers, and antisense RNAs.
What provides the energy for DNA polymerization in a PCR reaction?
Deoxyribonucleoside triphosphates
In gel electrophoresis, DNA molecules move toward the ________ electrode because they have an overall ________ charge.
positive; negative
Beta-carotene, the biochemical precursor to vitamin A, can be added to rice by using (biotechnology/cloning/recombinant) DNA technology, thereby increasing its nutritional value.
recombinant
If all the following DNA fragments were analyzed on an electrophoresis gel, which one would migrate farthest from the negative electrode?
250 base pairs
In which direction does DNA polymerase synthesize the new DNA strand?
5' to 3'
cDNA stands for __________.
complementary DNA
The enzyme reverse transcriptase
synthesizes DNA from an RNA template.
What is the function of the primers in PCR?
They provide a 3' end for the DNA polymerase
Which of the following is essential in PCR?
both DNA primers and DNA polymerase
Which of the following attaches the target gene to a desired location?
DNA ligase
Which of the following would be a likely cutting sequence for a restriction enzyme?
GTTAAC
Why would a recombinant DNA molecule be inserted into a host cell?
It can be copied, transcribed, and translated into a desired protein.
Why is DNA polymerase from Thermus aquaticus ideal for PCR?
It can withstand the high temperatures associated with PCR.
Which of the following is an application that uses PCR?
Sequencing a gene, diagnosing a disease, and providing enough DNA for cloning into another organism
A researcher mistakenly uses a heat-sensitive version of DNA polymerase in a PCR. Which of the following will occur?
The PCR will stop after one cycle
Which of the following is NOT a reason why human proteins can be synthesized in bacteria or yeast through genetic engineering?
The protein produced by microbes works better than the original protein.
How do restriction enzymes cut DNA sequences?
They cut DNA at sites, called recognition sites, that have specific nucleotide sequences.
In general, how might recombinant DNA technology be used to prevent a genetic disorder caused by a mutation in a single gene?
To insert a desirable gene, remove an undesirable gene, or replace a defective gene with a functioning gene
What is the end goal of PCR?
To quickly increase the number of copies of a specific DNA sequence
Reverse transcriptase synthesizes a DNA molecule from an RNA template.
True
Under ideal conditions, the number of DNA molecules produced during PCR increases exponentially.
True
The use of microbes to make practical products such as vaccines or hormones is called (genomics/recombination/biotechnology).
biotechnology
Transgenic organisms
contain genes from other organisms.
PCR stands for
polymerase chain reaction.
If a scientist wanted to view the location of a particular species of bacterium within a biofilm, which technique could be used?
fluorescent in situ hybridization (FISH)
DNA encoding a normal gene is inserted into cells from a patient with a defective form of the gene. Recombinant cells are identified and isolated, and returned to the patient's body. This is an example of
gene therapy.
Replacing a patient's defective gene with a fragment containing a functional gene is
gene therapy.
The sequencing and analysis of an organism's genetic information is called
genomics.
Which of the following is NOT a goal of recombinant DNA technology?
making it possible to clone humans
Which of the following procedures might be used to detect the presence of genetic sequences of a virus in a sample?
microarray or PCR
DNA microarrays can be used to __________.
monitor gene expression
Which of the following enzymes can make specific cuts in DNA molecules?
restriction enzymes
Synthesis of cDNA requires the use of
reverse transcriptase
Four different fluorescent dyes are used in automated DNA sequencing because __________.
there are four different nucleotides in DNA
