BIOL09020
August 2011
Answer THREE questions:
ONE question from Section A,
ONE question from Section B and
ONE other
Section A
Answer at least ONE question from this section.
1.
a) A DNA library is a useful resource for a scientist. Describe the
method(s) that would be used to create
i)
ii)
b)
2.
3.
a genomic library and
a cDNA library.
(50)
Describe a method to select a specific fragment of DNA with
a known sequence from a DNA library.
Write an account of the various types of mutations that can occur
and the effects they may have on the phenotype of an organism.
(100)
A new protein has been discovered which has the potential to be
used as a therapy for breast cancer. The first step is to clone the
gene for this protein. Describe the step(s) that might be performed
to clone the gene using a bacterial host.
(100)
Section B
Answer at least ONE question from this section
4.
a) The bacterial genome is smaller in size than the human
genome. Compare the organisation and content of both
genomes.
b)
5.
6.
(50)
(50)
It is essential that the replication of DNA is accurate. Discuss
the mechanisms that enable this to be achieved.
(50)
Genes are only expressed when the protein is required by the cell.
Discuss the mechanisms used in bacteria to control gene
expression.
(100)
Compare and contrast the process of translation in prokaryotes
and eukaryotes.
(100)
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BIOL09020
August 2011
Section A
Answer at least ONE question from this section.
1.
a) In gene cloning both the ligation step to create the
recombinant DNA and the transformation of bacteria with
recombinant DNA are inefficient. Discuss both the reasons
why and also any techniques that improve the efficiency.
b)
2.
3.
Describe two ways that bacteria transformed with
recombinant DNA can be separated from untransformed or
vector only transformed cells.
(50)
(50)
Discuss both the underlying mechanistic principle and some of the
uses of the polymerase chain reaction (PCR).
(100)
Write an account of the effects of genomic mutations with
reference to specific diseases
(100)
Section B
Answer at least ONE question from this section.
4.
A protein, called DBP50, has been isolated from cells. The
presence of this protein in the cell results in increased expression
of gene C. Structural studies have shown DBP50 to have a zinc
finger motif.
5.
6.
a)
Discuss the possible role of the protein, DBP50, in the cell.
(20)
b)
Discuss possible experiments that would give more
information about DBP50 and its relationship with gene C.
(80)
Compare and contrast the control of gene expression in
prokaryotes and eukaryotes.
(100)
Outline the mechanisms of DNA replication and repair.
(100)
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BIOL09020
August 2011
SECTION A
Answer at least ONE Question from this section
Q1
a)
A genomic library is a useful resource for a molecular biologist.
Outline the methods that can be used to create a genomic library
and how a library might be used to study genes.
(50)
b)
Compare and contrast the two types of DNA library that are
commonly used, namely genomic and cDNA libraries.
(50)
Q2
As a researcher you have been asked to clone the gene which codes for a
detoxification enzyme the group are working on. Describe the method you
would use to clone this gene using Esherichia coli as a host.
(100)
Q3.
‘Gene mutations can lead to cancer.’ Using specific examples discuss this
statement.
(100)
SECTION B
Answer at least ONE Question from this section
Q4
a)
The human genome contains many repetitive sequences. Describe
how these can be used to identify individuals.
(50)
b)
Describe the role of the enzyme telomerase in both normal and
cancerous cells.
(50)
Q5
Compare and contrast the process of transcription in prokaryotes and
eukaryotes.
(100)
Q6
Outline the structure of the lac operon of Escherichia coli and describe
the mechanism by which the operon is regulated in response to the
availability of lactose.
(100)
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