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Biotechnology: Chapter How Do We Use What We Know about Life?
1. Designer babies and gene therapy can be considered forms of biotechnology because:
a. both involve artificial manipulation of virus particles
b. both use tools and techniques for manipulating genetic material in organisms
c. both use counseling therapy to guide the decision making process
d. both can result in non-living forms created from living organisms
e. both use DNA technology for industrial purposes
Ans: b
2. In the 1960s the flow of cell functioning information in prokaryotic cells was identified as
a. transcription of DNA genetic information > translation of mRNA message -> formation of
proteins necessary for cell function
b. replication of DNA genetic information -> cell division - > cell division -> functioning cell
c. translation of mRNA message in nucleus to DNA genetic information which directs functioning of
cell
d. formation of proteins necessary for cell function -> assembly of DNA genetic code
e. transfer of DNA genetic information to alternate cells via plasmids which direct function of cell
Ans: a
3. All of the following contribute to the use of microbes or prokaryotic cells to study and manipulate
eukaryotic DNA EXCEPT:
a. microbes are small, inexpensive to maintain, and easy to house
b. microbes are quick to multiply in the laboratory
c. microbes can grow great quantities of a single DNA directed substance
d. the prokaryotic chromosome is simple and therefore easy to insert into eukaryotic DNA
e. microbe mutation provides the variation necessary for eukaryotic DNA cloning
Ans: e
4. All of the following can be used to describe a cloning vector EXCEPT
a. a cloning vector is a genetic hitchhiker
b. a cloning vector is a genetically engineered plasmid
c. virus can act as a cloning vector
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d. a cloning vector is an artificial lipid that can be used to control cell replication
e. a cloning vector is a vehicle that inserts a fragment of foreign DNA into the genome of a host cell
Ans: d
5. The technology of genetic engineering has revolutionized the pharmaceutical industry through
a. the ability to make generic drugs
b. the ability to use bovine proteins to treat disease
c. the ability to use bacteria cultures to produce mass quantities of a protein
d. the ability to use porcine proteins to treat disease
e. the ability to produce vaccine from viruses
Ans: c
6. Restriction enzymes or restriction endonucleases act as molecular
a. super glue
b. scissors
c. erasers
d. scribes
e. magnifiers
Ans: b
7. Sticky ends is a term that describes
a. the DNA that is left behind after bacteria have been removed from a culture plate
b. the unpaired DNA bases after the DNA has been exposed to a restriction enzyme
c. the bacterial strain that ends with the same initials as its corresponding restriction enzyme
d. the last sequence of a DNA strand that codes for STOP
e. the affinity of a restriction enzyme for a particular sequence on the DNA strand
Ans: b
8. Which enzyme is correctly matched with its function?
a. restriction enzyme: severs DNA at specific nucleotide sequences called restriction sites
b. restriction endonuclease: glues the two strands of DNA back together after replication
c. DNA ligase: cuts plasmid DNA in bacterial cells into one gene units
d. Palindromase: matches the nucleotide sequences of one strand of DNA to another
e. DNAase: repairs the hydrogen bonds that holds base pairs together in a DNA strand
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Ans: a
9. Agarose gel electrophoresis is a technology that allows
a. a gelatin substance to be used for separating nucleotides
b. an electrical charge to energize various protein molecules
c. a pattern to form from genes on a chromosome
d. the transfer of DNA from prokaryotic cells to eukaryotic cells
e. various sized fragments of DNA to be visualized
Ans: e
10. What is recombinant DNA?
a. Recombinant DNA is DNA formed by splicing RNA into existing DNA strands
b. Recombinant DNA is DNA formed by joining together DNA fragments of different organisms.
c. Recombinant DNA is DNA formed by rearranging the sequence of genes on a single strand of
existing DNA
d. Recombinant DNA is DNA formed from synthetic nucleotides
e. Recombinant DNA is DNA formed by replication of an existing DNA strand
Ans: b
11. A vehicle for carrying foreign DNA into a host bacterium is called
a. a vector
b. an ambassador
c. mRNA
d. a transport protein
e. a sedan
Ans: a
12. A mixture of DNA fragments has been separated using agarose gel electrophoresis. You would
expect to find
a. the largest size fragments closest to the point of origin
b. the smallest size fragments closest to the point of origin
c. the most dense fragments farther from the point of origin
d. the largest size fragments clumped together into one solid band
e. the smallest size fragments fluorescent and the larger size fragments not fluoresent
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Ans: a
13. A mixture of DNA fragments has been separated using agarose gel electrophoresis. The number
of bands resulting indicates
a. how many nucleotides were present in the mixture
b. how strong the electric current was that used to run the electrophoresis
c. how many different varieties of nucleic acids were present in the mixture
d. how many different-sized fragments of DNA were in the mixture
e. how many times the agarose gel unit was turned on and turned off
Ans: d
14. The term DNA library evokes an accurate analogy because
a. each fragment of DNA is cataloged similar to the Library of Congress system
b. each fragment of DNA can be checked out of circulation by a particular strain of bacteria
c. each fragment of DNA can be converted into large print or audio formats
d. each fragment of DNA is like a single volume in a library containing a million different books
e. each fragment of DNA can be read by multiple sources
Ans: d
15. The polymerase chain reaction (PCR)
a. makes billions of copies of small regions of DNA
b. allows specific sequences of DNA to be targeted from an entire genome and amplified
c. uses primers to line up with complementary bases on separated strands of DNA
d. all of the above
e. none of the above
Ans: d
16. What technique is used by forensic biologists to identify individuals or is used to establish
genetic relationships between individuals?
a. DNA sequencing
b. DNA fingerprinting
c. restitution
d. hypersequencing
e. locusing
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Ans: b
17. The exact order of nucleotides in a section of DNA can be determined through
a. DNA sequencing
b. DNA fingerprinting
c. DNA typing
d. hyperbole
e. DNAosis
Ans: a
18. Which of the following is NOT a long or short-term goal of the Human Genome project?
a. decipher the full set of genetic instructions in human DNA
b. develop the set of human genetic instructions as a research tool for scientists
c. provide a genetic map of the 24 different human chromosomes (22 autosomes and X & Y)
d. understand all of the genes, what they do, how they interact
e. reproduce the genetic instruction in a fruit fly or other model organism in humans
Ans: e
19. Computers designed to scan large amount of DNA sequence easily identify open reading frames
by locating
a. a repeating string of nucleotide bases
b. the AUG start codon and UGA stop codon
c. two equally spaced regions of DNA coding for the same amino acid order
d. a comparable DNA sequence published on the internet
e. sections of DNA that match the code for a specific gene
Ans: b
20. Positions within the genome where DNA nucleotides of 2 or more individuals differ, i.e., where
different nucleotides occupy the same position are called __________.
a. polypeptide protein parts (PPPs)
b. single nucleotide polymorphisms (SNPs)
c. snipets
d. unique nucleotide differentiators (UNDs)
e. palindromes
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Ans: b
21. Model organisms genomes have been sequenced as part of the Human Genome Project. The
model organisms are used in laboratories to study basic biological mechanisms. Which of the
following is not currently identified as a model organism today:
a. yeast
b. mustard plant (Arabidopsis)
c. nematode worm (C. elegans)
d. sea urchin (Echinodermata)
e. bacteria (E. coli)
Ans: d
22. What word describes stem cells from embryos that can give rise to any of the 210 different
human cells in the body? Such cells have an unlimited capability to differentiate.
a. total awesome
b. totidivertent
c. potential
d. totipotent
e. superpotent
Ans: d
23. Polymorphism is the principle on which DNA fingerprinting is based. Polymorphism means
a. multiple forms
b. numerous changes
c. several pieces of the whole
d. various narcotic drugs
e. single transformations
Ans: a
24. Many disorders are characterized by abnormalities in the structure of individual chromosomes.
The work of the Human Genome Project has allowed us to
a. see banding sequence of the stained chromosomes under a microscope to identify abnormal
chromosome structure
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b. correlate chromosomal abnormalities with the nucleotide sequences found at those damaged
chromosomal positions
c. artificially create chromosomal abnormalities
d. form a DNA donor pool to contribute to those with chromosomal abnormalities
e. legislate who gets normal chromosomes and who gets abnormal chromosomes
Ans: b
25. On March 24, 1989, the Exxon Valdez oil taker ran aground in Alaska spilling more than 10
million gallons of oil. To clean up the spill, naturally occurring bacteria capable of digesting
hydrocarbons were fertilized. This approach to cleaning the environment is:
a. bioremediation
b. biotia
c. bacteriobloom
d. deoiling
e. envirolism
Ans: a
26. What percentage of the human genome is actually coding DNA?
a. about 50%
b. about 10%
c. about 14%
d. about 3%
e. about 5%
Ans: d
27. Which of the following is not an argument raised in opposition to DNA technology
a. Using DNA technology to alter genes is unnatural
b. DNA technology breaches the fundamental boundaries between species
c. Using DNA technology interferes with the order of life, altering the evolutionary process
d. DNA technology is primarily a commercial undertaking to generate profit
e. DNA technology improves human well-being
Ans: e
28. What is meant by a palindromic DNA sequence? Give an example.
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Ans: A palindromic DNA sequence is one that is the same when it is read forward and backward and
upside down. Example: CCC
29. The cut made by most restriction endonucleases leave sticky ends. How does this feature aid
in joining two pieces of DNA from different sources?
Ans: Many restriction endonucleases cut DNA so that several unpaired nucleotide bases are left on
the ends of both DNA strands. These unpaired bases are often referred to as sticky ends. When two
pieces of DNA with the same sticky ends, which are complementary to each other, encounter one
another, the complementary sticky ends will hydrogen bond to each other, joining the two pieces of
DNA together. If DNA from two different sources, e. g., bacterial DNA and human DNA, is treated
with the same restriction enzyme, they will have complementary sticky ends and will be able to
adhere to each other via hydrogen bonds.
30. Molecular biologists can connect pieces of DNA from two different organisms to make
recombinant DNA. What are the steps in this process?
Ans: If the DNAs from the two different organisms are treated with the same restriction
endonuclease, they will be cut at the same recognition site and will possess the same sticky ends. If
the two types of DNA are mixed, their sticky ends will pair with each other, hooking together the
two foreign pieces of DNA. The association can be made permanent by treating the recombinant
DNA with the enzyme DNA ligase, which will connect the two foreign pieces of DNA covalently.
31. What is the natural function of restriction enzymes in bacteria?
Ans: These enzymes evolved as a mechanism for ridding bacteria of unwanted DNA from viruses
and other invaders. They cut the unwanted DNA into fragments that can be digested and removed
by the bacterial cell.
32. Why does DNA travel toward the positive electrode through an agarose gel?
Ans: The backbone of a DNA polynucleotide is negatively charged since each nucleotide contains a
negatively charged phosphate group. Thus, it is attracted to the positive electrode, the cathode.
33. How do investigators determine the size of DNA fragments from agarose gel electrophoresis?
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Ans: The size of DNA fragments is estimated by comparing their band positions on a gel with the
positions of standards which are DNA fragments of known applied size to a different well on the
same gel. The standards act as a control model for DNA movement.
34. What is a cDNA library? A cDNA library is a library that includes those genes expressed in a
particular cell type or at a particular time during development. Why is such a library more
manageable than a genomic library?
Ans: Since it reflects only those genes active in a particular cell or those genes active at a particular
time rather than the total genetic complement of the organism, the number of genes represented is
greatly reduced and so is the number of fragments in the library. This reduction will make the
library more manageable.
35. What is the polymerase chain reaction or PCR?
Ans: Using the polymerase chain reaction or PCR, specific sequences of DNA can be targeted from
the entire genome and amplified, copied billions of times, without first cutting with restriction
enzymes or cloning. It is possible to make billions of copies of a sequence of DNA nucleotides that
may be present initially in very few copies. What must one know before performing PCR? One
must know what the target DNA is, that is, which part of the total DNA one wishes to copy. One
must also know the nucleotide sequences of about 20 bases on either side of the target DNA, its
flanking sequences.
36. What are the primers in PCR and why are they needed?
Ans: Primers are short DNA strands complementary to the flanking regions of target DNA in the
polymerase chain reaction (PCR). DNA polymerase, the enzyme that synthesizes new DNA
polymers, cannot initiate a new DNA strand. It can only add nucleotides to a strand that is already
started. The primers provide the free end to which DNA polymerase can add nucleotides.
37. What features would help an investigator to identify a DNA sequence as an open reading frame
or an ORF?
Ans: If a DNA sequence has a start signal and a promoter sequence followed by a sufficient length
of amino acid-encoding triplets to form a protein and a stop signal, one would characterize it as an
open reading frame or an ORF.
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38. What has the Human Genome Project told us about human origins, history and evolution?
Ans: Early results from the Human Genome Project suggest that humans originated in Africa and
branched out to other continents about 150,000 years ago. These results confirm theories of human
expansion that have been developed by anthropologists.
39. Discuss one long term goal and one short term goal of the Human Genome Project
Ans: One of the long-term goals of the Human Genome Project is that we hope to learn the role of
each gene and even the vast stretches of DNA that have no genes. We also hope that continued
studies of SNPs may uncover the genetic basis of our particular talents & susceptibilities.
Furthermore, studies may enable physicians to predict individual responses to medicines,
environmental influences and lifestyles.
40. Name two ways in which stem cells differ from other cells of the body?
Ans: First, stem cells are uncommitted. They are capable of dividing and their progeny might give
rise to any number of different kinds of cells. Other body cells are committed to a relatively limited
fate and will give rise to cells essentially similar to themselves. Second, stem cells can grow and
divide in laboratory cultures indefinitely. Other human cells might divide a few times in culture, but
they eventually stop dividing and die after a few generations.
41. Describe one way that agricultural biotechnology being used to improve agriculture?
Ans: Agricultural biotechnology is being used to increase world food production while decreasing
the cost and environmental damage related to insecticide and herbicide use. Crops are being
developed that are able to fend off insect pests without the use of insecticides. Plants are also being
engineered to give a greater yield and to grow in a wider range of climatic conditions, including hot,
dry climates. Crops are also being engineered to be resistant to herbicides, so that fields can be
treated for plant pests without damaging crops.
42. Genetically modified food has raised concerns from citizen groups. What are two of those
concerns?
Ans: Risk to human health and risks to the environment.
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43. What are VNTRs or variable number tandem repeats?
Ans: VNTRs are non-coding genome regions within which short DNA sequences called core
sequences are repeated hundreds or perhaps thousands of times. The number of core sequence
repeats varies from person to person.
44. Dolly was the first cloned sheep. Outline the steps taken to produce Dolly, a Dorset lamb from
two ewes one Dorset and one Scottish blackface.
Ans: Adult cells from a Dorset ewe were taken from the sheeps udder. An egg was harvested from
a Scottish blackface ewe. The DNA was removed with a needle. The two cells were fused with a
mild electrical shock. The fused cell was transplanted to the womb of a Scottish blackface who gave
birth to Dolly.
45. Which of the following would NOT be considered a tool in the DNA technology toolbox?
a. restriction enzymes to cut DNA in specific places
b. DNA ligase to connect different DNAs to make recombinant molecules
c. Genetically engineered plasmids to carry foreign DNA into bacteria for replication
d. Vectors to carry foreign DNA into bacteria
e. Punnett square for calculating probability of parental genetic combinations
Ans: e
46. BLAST stands for Basic Local Alignment Search Tool and is the gateway to published databases
of nucleotide sequences. As a scientist, BLAST is very useful to you by providing:
a. A match of a nucleotide sequence from an unknown organism with that of all known nucleotide
sequences from every type of organism for which such information exists
b. The name of the chromosome on which the particular nucleotide sequence resides
c. The locus on the chromosome for which a particular nucleotide sequence codes
d. A match of two unknown nucleotide sequences
e. A comparison of vectors known to carry particular nucleotide sequences
Ans: a
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47. Plasmids and viruses are excellent vectors for transferring small bits of DNA into host cells.
What vectors have been engineered for getting large fragments of DNA into bacteria and other
hosts?
a. cosmids which can insert as many as 35 to 45 thousand base pairs
b. yeast artificial chromosomes (YAC) which can insert up to 200 thousand base pairs
c. HIV which can insert 5 10 thousand base pairs
d. Bacillus subtilis which can insert entire stands of DNA
e. Both a and b
Ans: e
48. What element is missing from a cDNA library that is included in a genomic library?
a. The cDNA library is missing the small portion of a cells DNA which is actually expressed
b. The cDNA library is missing only those genes that are expressed for a particular cell type
c. The cDNA library is missing only those genes that are expressed at a particular time
d. The cDNA library is missing the DNA fragments representing the entire genome of an organism
e. The cDNA library is identical to a genomic library.
Ans: d
49. Model organisms are useful for probing certain kinds of biological questions. Supermodels such
as ematodes and mustard plants have been used to describe
a. gene expression
b. transcription
c. translation
d. gene regulation
e. all of the above
Ans: e
50. What are embryonic stem cells?
a. stem cells are the precursor cell from which blood cells are derived
b. stem cells are undifferentiated cells from which specialized cells develop
c. embryonic stem cells are cells that have the ability to proliferate indefinitely
d. embryonic stem cells are derived from fertilized embryos
e. all of the above
Ans: e
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51. Biotechnology is changing the way we live. All of the following are now possibilities provided
through biotechnology EXCEPT:
a. identify the perpetrator of a crime
b. design new drugs to treat disease
c. change the appearance of solar planets
d. develop drought-resistant crops
e. lengthen the shelf life of fruit
Ans: c
52. In order to match a hair follicle found at the scene of a crime with the suspects hair, scientists
from CSI must complete a DNA analysis. The following steps in DNA analysis are out of order.
What is the first step of the process and the last step?
I.
Agarose Gel Electrophoresis of DNA fragments
II.
Addition of restriction enzymes
III.
PCR amplification
IV.
DNA extraction
V.
Prepare Autoradiograph to identify the criminal
VI.
Hybridize with VNTR Radioactive Probe
VII. Hybridize with additional VNTR Probes
VIII. Southern Blotting
a. First step is IV; Last is VIII
b. First step is I; Last is IV
c. First step is IV; Last is V
d. First step is III; Last is VII
e. First step is II; Last is V
Ans: c
53. In DNA analysis, what method is used to separate extracted DNA from cellular debris?
a. Vector
b. Centrifugation
c. Amplification
d. Electrophoresis
e. Restriction enzyme
Ans: b
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54. Name one pro and one con in the great debate over stem cell research.
Ans: Pro stem cell research:scientists believe stem cells from human embryos could hold the key to
treatments and cures for disease. Anti-stem cell research: Pro-life advocates argue using the cells is
the equivalent of taking a life, even if it is to save a life.
55. How has the Bt-engineered corn endangered the monarch butterfly?
Ans: It has been discovered that pollen from Bt corn is toxic to the monarch butterfly. Corn pollen
gets airborne and is blown into milkweed patches. When monarchs feed on the milkweed, they
ingest the Bt pollen, which poisons and kills them.
56. In the Southern blot apparatus, in what direction does the transfer solution move and what does
its movement accomplish?
Ans: The transfer solution moves up from the glass baking dish through the Whatman filter paper
wicks, into and through the agarose gel and then into the nitrocellulose filter or the nylon membrane.
From there, it goes into more filter paper and the paper towels always traveling up. As the transfer
solution, travels through the gel, it carries the DNA in the gel onto the nitrocellulose or nylon
membrane just above. The DNA sticks to the nitrocellulose/nylon membrane and its position on the
membrane mirrors the position it occupied in the gel since the DNA had traveled straight up along
with the transfer solution.
57. You are part of a research team of plant biologists. Your job is to identify plants which have
drought-tolerant genes, isolate those genes, and transfer them to an appropriate vector. Why are you
treating the plasmid vector and the DNA containing the drought-tolerant gene with the same
restriction enzyme?
Ans: If both pieces of DNA are treated with the same restriction enzyme, each cut in either piece of
DNA will have the same set of sticky ends. Since pieces of DNA with the same sticky ends can join
by base pairing, this allows the formation of a recombinant DNA. If the two DNA preparations had
been treated with different restriction enzymes that recognize different sites in the DNA, they could
not have been joined.
58. Describe two other hazards to monarch butterfly survival besides the toxicity of Bt corn pollen.
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Ans: Habitat destruction by logging, spraying of herbicides for weed control and habitat alteration
which reduced habitat and food sources for the monarch are all hazards to monarch survival. Urban
sprawl and mowing highway right of ways also destroy the milkweed plant which is a food source
for the monarch.
59. Support the argument that the genome of model organisms are almost as valuable to scientists as
the human genome.
Ans: Each model organism whose genome has been sequence provide insights into the mechanisms
of gene expression, gene regulation and gene encoding. The understanding of these processes can be
applied to human models.
60. Biotechnology is a relatively new field. Identify two potential risks of biotechnology and discuss
the concerns.
Ans: Potential risks of biotechnology include its possible adverse effects on biological diversity.
The areas of concern include adverse changes in competitiveness, virulence or other characteristics
of the target species as well as adverse impacts on non-target species such as beneficial insects and
ecosystems. Another risk of biotechnology is the potential danger to human health. There are those
foods, such as corn or soybeans that have been modified to incorporate the genes of bacteria that are
deadly to crop pests. Skeptics wonder whether the same bacterial genes might not eventually prove
harmful to humans as well.
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