Transcript 12_Active_Lecture_Questions

Chapter 12
DNA Technology and Genomics
Active Lecture Questions for
Biology: Concepts & Connections, Sixth Edition
Campbell, Reece, Taylor, Simon, and Dickey
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Concept Check
Restriction enzymes are useful tools for cutting DNA
fragments. What is the function of restriction enzymes in their
normal bacterial environment?
1)
Restriction enzymes remove and recycle old mRNA’s.
2)
Restriction enzymes cut up DNA taken from the
environment and used as a nutrient source.
3) Restriction enzymes remove the excess DNA that results
from DNA replication.
4)
Restriction enzymes cut invading viral DNA sequences
at specific sequences disrupting the viral DNA genes.
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Answer
Restriction enzymes are useful tools for cutting DNA
fragments. What is the function of restriction enzymes in their
normal bacterial environment?
4)
Restriction enzymes cut invading viral DNA sequences
at specific sequences disrupting the viral DNA genes.
Copyright © 2009 Pearson Education, Inc.
Concept Check
PCR or polymerase chain reaction amplifies target DNA fragments.
This technique takes place outside of a cell and uses heat to
separate the double stranded DNA along with which of the
following?
1)
Restriction enzymes from E. coli bacteria
2)
DNA polymerase isolated from bacteria from hot springs
3)
Radioactive probes
4)
Plasmids from E. coli or other bacteria
Copyright © 2009 Pearson Education, Inc.
Answer
PCR or polymerase chain reaction amplifies target DNA fragments.
This technique takes place outside of a cell and uses heat to
separate the double stranded DNA along with which of the
following?
2)
DNA polymerase isolated from bacteria from hot springs
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Interpreting Data
The image to the right represents a
simulated electrophoresis gel run of a
restriction analysis of λ virus DNA.
Both EcoR1 (E) and BamH1 (B) cut λ
DNA into 6 fragments. Why aren’t the
fragments aligned together on the gel?
1) The enzymes cut at random sites
each time.
2)
The enzymes each cut at unique
restriction sites that create
differently sized fragments.
3)
The two enzymes create equal
sized fragments but the gel
cannot resolve the difference.
Copyright © 2009 Pearson Education, Inc.
Answer
The image to the right represents a
simulated electrophoresis gel run of a
restriction analysis of λ virus DNA.
Both EcoR1 (E) and BamH1 (B) cut λ
DNA into 6 fragments. Why aren’t the
fragments aligned together on the gel?
2)
The enzymes each cut at unique
restriction sites that create
differently sized fragments.
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Interpreting Data
The fourth column (H) is λ DNA cut
with HindIII enzyme. It serves as a
ruler to estimate the size of the other
fragments. How long (in base pairs)
do you estimate the shortest EcoR1
(E) fragment to be?
1)
2000 bp
2) 2300 bp
3)
3500 bp
4)
4300 bp
Copyright © 2009 Pearson Education, Inc.
Answer
The fourth column (H) is λ DNA cut
with HindIII enzyme. It serves as a
ruler to estimate the size of the other
fragments. How long (in base pairs)
do you estimate the shortest EcoR1
(E) fragment to be?
3)
3500 bp
Copyright © 2009 Pearson Education, Inc.
Interpreting Data
The third column was loaded with λ
DNA that was cut with both EcoR1 and
BamH1 enzymes together. This creates
a number of additional fragments.
Which EcoR1 fragment does not have
a BamH1 cut site?
1)
The first fragment from the top.
(the largest)
2)
The second fragment from the
top.
3)
The second to the bottom
fragment.
4)
The bottom fragment. (the
smallest)
Copyright © 2009 Pearson Education, Inc.
Answer
The third column was loaded with λ
DNA that was cut with both EcoR1 and
BamH1 enzymes together. This creates
a number of additional fragments.
Which EcoR1 fragment does not have
a BamH1 cut site?
4)
The bottom fragment. (the
smallest)
Copyright © 2009 Pearson Education, Inc.
Biology and Society
This is a DNA microarray—an incredibly powerful tool to explore
gene expression in cells. Microarrays also have the potential to
be used to diagnose and predict the onset of debilitating diseases
such as cancer. There is much promise for this technology but
who has access to this information? Assume that the technology
exists today that could screen your specific DNA genome for
cancer risk.
In this scenario do you think that insurance companies
would be justified requiring a DNA screen for cancer upon
application for health or life insurance?
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Biology and Society
DNA technology has
revolutionized forensic science.
Some states have required
DNA samples for all convicted
felons. Some consider this to
be an infringement on personal
rights and freedoms. Several
unsolved cases have been
solved with this type of
evidence and some convicted
persons have been exonerated
with DNA evidence.
Do you think that states should create and maintain DNA
databases similar to fingerprint databases?
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Biology and Society
Do a web-search on “Golden
Rice” and you’ll be astounded
at the diversity of opinion and
information on this particular
genetically modified organism
(GM). Agricultural scientists
are increasingly turning to
genetic engineering to develop
new crop solutions and yet
around the world GM crops
are not universally accepted.
Do you think food products that are produced from GM
organisms should be labeled to inform consumers?
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