Transcript Chapter 2

Active Lecture Questions for
BIOLOGY, Eighth Edition
Neil Campbell & Jane Reece
Chapter 18
Regulation of Gene Expression
Questions prepared by
Louise Paquin,
McDaniel College
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings.
Operon
What elements from the following list constitute a
bacterial operon?
a) structural gene(s)
b) repressor gene
c) promoter
d) operator
e) inducer
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings.
Gene Regulation
Each of a group of bacterial cells has a mutation in
its lac operon. Which of these will make it
impossible for the cell to metabolize lactose?
a) mutation in lacZ (β-galactosidase gene)
b) mutation in lacI (cannot bind to operator)
c) mutation in promoter (cannot bind polymerase)
d) mutation in operator (cannot bind repressor)
e) mutation in lacI (cannot bind inducer)
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings.
When
At which stages of gene expression are bacteria
usually regulated?
Eukaryotes?
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings.
Transcription Factors
General transcription factors in eukaryotes are
needed for all genes using the same RNA
polymerase. What is the function of specific
transcription factors? Of enhancers?
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings.
Alternative Products
A specific gene is known to code for three different
but related proteins. This could be due to which of
the following?
a) premature mRNA degradation
b) alternative RNA splicing
c) use of different enhancers
d) protein degradation
e) differential transport
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings.
miRNA
A given RNA transcript forms
numerous hairpin loops that
are cut (diced) to form short
double-stranded non-coding
sequences.
How can these resulting
strands affect gene
expression?
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings.
Developmental Regulation
In the development of a multicellular organism,
differential gene expression is responsible for both
differentiation and sequential regulation. Write a
plausible hypothesis for how one of these could
occur in the formation of the heart.
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Embryo Formation
Scientists showed that bicoid mRNA, and then its
Bicoid protein, is normally found in highest
concentration at the fly’s anterior. Predict what
would happen if Bicoid were injected at the
posterior end.
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Oncogenes
Which of the following would not typically cause a
proto-oncogene to become an oncogene?
a) gene suppression
b) translocation
c) amplification
d) point mutation
e) retroviral activation
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings.
Multistep Cancer Causation
How does the multistep model of colorectal cancer
illustrate how an individual might inherit a
“predisposition” for a particular type of cancer?
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings.