Transcript File - jj-sct

CAMPBELL
BIOLOGY
TENTH
EDITION
Reece • Urry • Cain • Wasserman • Minorsky • Jackson
20
DNA Tools and
Biotechnology
Clicker Questions by
Roberta Batorsky
© 2014 Pearson Education, Inc.
The photograph shows Rainbow and CC (CC is
Rainbow’s clone). Why is CC’s coat pattern different
from Rainbow’s given that CC and Rainbow are
genetically identical?
a) random X chromosome
inactivation
b) heterozygous at coat
color gene locus
c) environmental effects
on gene expression
d) all of the above
© 2014 Pearson Education, Inc.
The photograph shows Rainbow and CC (CC is
Rainbow’s clone). Why is CC’s coat pattern different
from Rainbow’s given that CC and Rainbow are
genetically identical?
a) random X chromosome
inactivation
b) heterozygous at coat
color gene locus
c) environmental effects
on gene expression
d) all of the above
© 2014 Pearson Education, Inc.
Which is an incorrect statement about STRs (Short
Tandem repeats)?
a) They are tandemly repeated units of 5- to 10
nucleotide sequences
b) The number of repeats is polymorphic from person
to person
c) Two alleles of an STR may differ in an individual
d) They occur in specific regions of the genome
e) PCR is used to amplify particular STRs.
© 2014 Pearson Education, Inc.
Which is an incorrect statement about STRs (Short
Tandem repeats)?
a) They are tandemly repeated units of 5- to 10
nucleotide sequences
b) The number of repeats is polymorphic from person
to person
c) Two alleles of an STR may differ in an individual
d) They occur in specific regions of the genome
e) PCR is used to amplify particular STRs.
© 2014 Pearson Education, Inc.
Which of the following beneficial traits have not resulted
from DNA technology and genetic engineering of crop
plants?
a) Delayed ripening
b) Resistance to drought
c) Resistance to herbicides
d) Resistance to salinity
e) Superweeds
© 2014 Pearson Education, Inc.
Which of the following beneficial traits have not resulted
from DNA technology and genetic engineering of crop
plants?
a) Delayed ripening
b) Resistance to drought
c) Resistance to herbicides
d) Resistance to salinity
e) Superweeds
© 2014 Pearson Education, Inc.
Which of the following is not a correct statement about
third generation sequencing?
a) A single DNA molecule is sequenced on its own
b) Different bases interrupt an electric current for a
particular length of time a compound and an isotope;
a molecule
c) DNA moves through a small nanopore a molecule
and a compound; a molecule
d) DNA must be cut into fragments or amplified
© 2014 Pearson Education, Inc.
Which of the following is not a correct statement about
third generation sequencing?
a) A single DNA molecule is sequenced on its own
b) Different bases interrupt an electric current for a
particular length of time a compound and an isotope;
a molecule
c) DNA moves through a small nanopore a molecule
and a compound; a molecule
d) DNA must be cut into fragments or amplified
© 2014 Pearson Education, Inc.
Place the steps in a cycle of PCR (Polymerase Chain
Reaction) in the correct order:
1. Annealing—Cool to allow primers to form hydrogen
bonds with ends of target sequence
2. Extension—DNA polymerase adds nucleotides to the
3 end of each primer
3. Denaturation—Heat briefly to separate DNA strands
a) 3-1-2
b) 3-2-1
c) 1-2-3
d) 2-3-1
e) 1-3-2
f)
2-1-3
© 2014 Pearson Education, Inc.
Place the steps in a cycle of PCR (Polymerase Chain
Reaction) in the correct order:
1. Annealing—Cool to allow primers to form hydrogen
bonds with ends of target sequence
2. Extension—DNA polymerase adds nucleotides to the
3 end of each primer
3. Denaturation—Heat briefly to separate DNA strands
a) 3-1-2
b) 3-2-1
c) 1-2-3
d) 2-3-1
e) 1-3-2
f)
2-1-3
© 2014 Pearson Education, Inc.
Which of the following is an example of “recombinant
DNA”?
a) combining alternate alleles of a gene in a
single cell
b) manipulating a meiotic crossing-over event
c) cloning genes from homologous pairs of
chromosomes
d) introducing a human gene into a bacterial plasmid
e) alternate alleles assorting independently
© 2014 Pearson Education, Inc.
Which of the following is an example of “recombinant
DNA”?
a) combining alternate alleles of a gene in a
single cell
b) manipulating a meiotic crossing-over event
c) cloning genes from homologous pairs of
chromosomes
d) introducing a human gene into a bacterial
plasmid
e) alternate alleles assorting independently
© 2014 Pearson Education, Inc.
This segment of DNA is cut at restriction sites 1 and 2,
which creates restriction fragments A, B, and C. Which
of the following electrophoretic gels represents the
separation of these fragments?
a)
b)
c)
d)
© 2014 Pearson Education, Inc.
This segment of DNA is cut at restriction sites 1 and 2,
which creates restriction fragments A, B, and C. Which
of the following electrophoretic gels represents the
separation of these fragments?
a)
b)
c)
d)
© 2014 Pearson Education, Inc.
Scientific Skills Exercise
There is a lot of information in the figure on the next slide.
1) The top diagram depicts the very large regulatory region upstream
of the Hoxd13 gene. The area between the slashes represents the
DNA located between the promoter and the regulatory region.
2) The diagrams to the left of the bar graph show, first, the intact DNA
and, next, the three altered DNA sequences. A red X indicates the
segment (A, B, and/or C) that was deleted in each line of transgenic
mice.
3) The horizontal bar graph shows the amount of Hoxd13 mRNA that
was present in the digit-formation zone of each transgenic 12.5-dayold embryo paw relative to the amount that was in the digit-formation
zone of a wild-type mouse that had the intact regulatory region (top
bar = 100%). The paw images have blue stain visible where
the Hoxd13 mRNA is located.
© 2014 Pearson Education, Inc.
© 2014 Pearson Education, Inc.
Which of the four treatments was the control for the
experiment?
a) the wild-type mouse C
b) the transgenic mouse with all three segments
deleted N
c) the transgenic mouse with segments B and C
deleted
d) the transgenic mouse with only segment C deleted
© 2014 Pearson Education, Inc.
Which of the four treatments was the control for the
experiment?
a) the wild-type mouse C
b) the transgenic mouse with all three segments
deleted N
c) the transgenic mouse with segments B and C
deleted
d) the transgenic mouse with only segment C deleted
© 2014 Pearson Education, Inc.
The hypothesis was that all three segments of the
regulatory region are required for highest expression of
the Hoxd13 gene. Is this hypothesis supported by the
results?
a) Yes; when any of the segments were deleted, the
expression level dropped to less than 100% of the
control.
b) No; they did not delete the promoter, so the gene
could still be expressed even without the segments.
c) Yes; when all three segments were present, the
expression level was at 100%.
d) No; even when segments were deleted,
the Hoxd13 gene was still being expressed.
© 2014 Pearson Education, Inc.
The hypothesis was that all three segments of the
regulatory region are required for highest expression of
the Hoxd13 gene. Is this hypothesis supported by the
results?
a) Yes; when any of the segments were deleted, the
expression level dropped to less than 100% of
the control.
b) No; they did not delete the promoter, so the gene
could still be expressed even without the segments.
c) Yes; when all three segments were present, the
expression level was at 100%.
d) No; even when segments were deleted,
the Hoxd13 gene was still being expressed.
© 2014 Pearson Education, Inc.
What was the effect on the amount of Hoxd13 mRNA
when segments B and C were both deleted?
a) Only about 60% of the control amount of Hoxd13
mRNA was produced.
b) The deletion of segments B and C had no effect on
the amount of Hoxd13 mRNA produced.
c) Only about 35% of the control amount of Hoxd13
mRNA was produced.
d) Only about 5% of the control amount of Hoxd13
mRNA was produced.
© 2014 Pearson Education, Inc.
What was the effect on the amount of Hoxd13 mRNA
when segments B and C were both deleted?
a) Only about 60% of the control amount of Hoxd13
mRNA was produced.
b) The deletion of segments B and C had no effect on
the amount of Hoxd13 mRNA produced.
c) Only about 35% of the control amount of Hoxd13
mRNA was produced.
d) Only about 5% of the control amount of Hoxd13
mRNA was produced.
© 2014 Pearson Education, Inc.
Look at the blue stain in the in situ hybridization for the
transgenic mouse lacking segments B and C. How
would you describe the spatial pattern of gene
expression in the embryo paw as compared to the
control?
a) There is very light blue stain in the center of each
digit zone as compared to the control.
b) The blue stain is generally lighter than in the control,
but all four digit zones are still visible.
c) There is almost no blue stain anywhere in the paw
as compared to the control.
d) There is no blue stain at the base of the paw as
compared to the control.
© 2014 Pearson Education, Inc.
© 2014 Pearson Education, Inc.
Look at the blue stain in the in situ hybridization for the
transgenic mouse lacking segments B and C. How
would you describe the spatial pattern of gene
expression in the embryo paw as compared to the
control?
a) There is very light blue stain in the center of each
digit zone as compared to the control.
b) The blue stain is generally lighter than in the
control, but all four digit zones are still visible.
c) There is almost no blue stain anywhere in the paw
as compared to the control.
d) There is no blue stain at the base of the paw as
compared to the control.
© 2014 Pearson Education, Inc.
What was the effect on the amount of Hoxd13 mRNA
when just segment C was deleted?
a) The deletion of segment C had no effect on the
amount of Hoxd13 mRNA produced.
b) Only about 60% of the control amount of Hoxd13
mRNA was produced.
c) Only about 35% of the control amount of Hoxd13
mRNA was produced.
d) Only about 5% of the control amount of Hoxd13
mRNA was produced.
© 2014 Pearson Education, Inc.
What was the effect on the amount of Hoxd13 mRNA
when just segment C was deleted?
a) The deletion of segment C had no effect on the
amount of Hoxd13 mRNA produced.
b) Only about 60% of the control amount of Hoxd13
mRNA was produced.
c) Only about 35% of the control amount of Hoxd13
mRNA was produced.
d) Only about 5% of the control amount of Hoxd13
mRNA was produced.
© 2014 Pearson Education, Inc.
How would you describe the spatial pattern of gene
expression in the embryo paw lacking segment C as
compared to the control and to the paw lacking
segments B and C?
a) The digit zones are not visibly stained as they are in
the control and the paw lacking B and C.
b) The top of the paw is stained darker than both the
control and the paw lacking B and C.
c) The base of the paw is stained darker than both the
control and the paw lacking B and C.
d) The digit zones are defined with darker stain than
both the control and the paw lacking B and C.
© 2014 Pearson Education, Inc.
How would you describe the spatial pattern of gene
expression in the embryo paw lacking segment C as
compared to the control and to the paw lacking
segments B and C?
a) The digit zones are not visibly stained as they
are in the control and the paw lacking B and C.
b) The top of the paw is stained darker than both the
control and the paw lacking B and C.
c) The base of the paw is stained darker than both the
control and the paw lacking B and C.
d) The digit zones are defined with darker stain than
both the control and the paw lacking B and C.
© 2014 Pearson Education, Inc.
Suppose the researchers had only measured the
amount of Hoxd13 mRNA and not done the in
situ hybridizations. What important information about
the role of the regulatory segments would have been
missed?
a) The interaction of the regulatory region with the
promoter would have been missed.
b) The interaction among the different segments of the
regulatory region would have been missed.
c) The mRNA would not have been blue; therefore it
could not have been measured for the results shown
in the bar graph.
d) The spatial patterns of Hoxd13 gene expression in
the paws would have been missed.
© 2014 Pearson Education, Inc.
Suppose the researchers had only measured the
amount of Hoxd13 mRNA and not done the in
situ hybridizations. What important information about
the role of the regulatory segments would have been
missed?
a) The interaction of the regulatory region with the
promoter would have been missed.
b) The interaction among the different segments of the
regulatory region would have been missed.
c) The mRNA would not have been blue; therefore it
could not have been measured for the results shown
in the bar graph.
d) The spatial patterns of Hoxd13 gene expression
in the paws would have been missed.
© 2014 Pearson Education, Inc.
Suppose the researchers had only done the in
situ hybridizations and not measured the amount
of Hoxd13 mRNA. What important information would
have been missed?
a) The information about which regulatory segments
were deleted would have been missed.
b) The spatial patterns of Hoxd13 gene expression in
the paws would have been missed.
c) Qualitative data about Hoxd13 mRNA levels would
have been missed.
d) Quantitative data about Hoxd13 mRNA levels would
have been missed.
© 2014 Pearson Education, Inc.
Suppose the researchers had only done the in
situ hybridizations and not measured the amount
of Hoxd13 mRNA. What important information would
have been missed?
a) The information about which regulatory segments
were deleted would have been missed.
b) The spatial patterns of Hoxd13 gene expression in
the paws would have been missed.
c) Qualitative data about Hoxd13 mRNA levels would
have been missed.
d) Quantitative data about Hoxd13 mRNA levels
would have been missed.
© 2014 Pearson Education, Inc.