name:_______________________
student ID:_____________________
Genetics L311 exam 3
April 10, 2015
Directions: Please read each question carefully. Answer questions as concisely as possible.
Excessively long answers, particularly if they include any inaccuracies, may result in deduction
of points. You may use the back of the pages as work sheets, but please write your answer in the
space allotted. However, you must show all your work. Clearly define your genetic symbols.
We will not make guesses as to what a particular symbol is intended to mean. Also, don’t assume
that strains are true-breeding unless this is stated in the question. Finally, show all your work.
Good luck.
page 2
_______
(20 points possible)
page 3
_______
(22 points possible)
page 4
_______
(26 points possible)
page 5
_______
(17 points possible)
page 6
_______
(15 points possible)
total
_______ (of 100 points possible)
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name:_______________________
student ID:_____________________
1. Short answers (2 points each, 20 points total)
A. The ability of some bacteriophage to transfer any sufficiently small portion of
bacterial chromosome from one strain to another is
.
B. A(n)
is a special type of rearrangement in which the
long arms of two acrocentric chromosomes fuse.
C. In
the duplicate chromosome complement is
composed of multiple sets of chromosomes derived from a single species.
D. A genetic element that can exist either free in the cytoplasm or integrated into the
chromosome is a(n)
.
E. The procedure where protein is isolated from cells, separated by SDS-PAGE,
transferred to membrane, incubated with a protein-specific antibody and then the
antibody detected in some way is called a
.
F. The region of a bacterial cell in which the genome resides, which is not separated from
the cytoplasm by a membrane, is called the
.
G. Deviation from a whole number multiple of the haploid chromosome complement
produces
.
Please provide concise definitions of the following terms:
H. reverse genetics:
I. reporter transgene:
J. RNAi:
2
name:_______________________
student ID:_____________________
2. While exploring an island off the coast of Costa Rica, you discover a dinosaur thought long
extinct, called Tejpalasaurus rex, which you take home as a pet. After growing attached, you
decide to clone him. Assume you have access to all things you need to do this and that the
method discussed in class will work with dinosaurs.
A. Briefly explain how you would go about cloning this animal (6 points).
B. List four reasons why the clones won’t be exactly identical to your original pet dino (6
points).
C. You manage to make several clones of Tejpalasaurus rex. Surprisingly a karyotype analysis
of your clones found some with unusual chromosome counts. T. rex normally has 39 pairs of
chromosomes (i.e. 2n = 78). Fill in the blanks for each of the variants in the table below (10
points):
# chromosomes
79
ploidy of
individual
triploid
39
tetraploid
monosomic
3
name:_______________________
student ID:_____________________
3A. Your studies of magical talent in British Potter family leads to a remarkable discovery. You
find that a single gene, mgc, confers magical abilities. Miraculously you manage to purify the
MGC protein and obtain amino acid sequence of a portion of the protein. Name the strategy that
you will use and briefly explain how you would go about cloning the mgc gene (8 points)?
B. After cloning the mgc gene you want to know where it is expressed. You cannot easily
address this question in humans so you clone the mouse mgc gene. Explain how you would use
the mouse mgc gene to study where it is expressed in mouse. Include the relevant steps and
diagram the vector (8 points).
4. In the rare dancing lemur of Madagascar, S. reifeisae, you observe two distinct phenotypes:
golden fur and brown fur. To study the transmission of this trait you perform crosses that yield
the results shown below.
Golden female X Brown male
All Golden
Cross siblings
All Golden
Cross siblings
Golden and Brown
A. Name and describe the type of inheritance determining the fur color in these lemurs (6
points).
B. What phenotypic ratio is observed in the F3 generations (4 points)?
4
name:_______________________
student ID:_____________________
5. You are studying the wild tickling monkey N. kumarae. You want to find out why these
creatures are filled with an insatiable desire to tickle others when in large groups. After several
bouts of fierce tickling you are able to obtain some hair for genetic testing from several
individuals in different troupes. You find that the different troupes have different forms of
chromosome 6 present.
A. Determine the order in which the changes occurred and the name of the rearrangement (8
points).
original
chromosome
strain I
strain II
strain III
strain IV
B. Please diagram synapsis of chromosome 6 in an individual heterozygous for a strain II and a
strain III chromosome (3 points).
6. The production of transgenic crop plants, sometimes referred to as genetically modified plants,
is controversial in some places in the world. Please list three potential benefits to engineering
such crops and three potential concerns associated with their widespread cultivation (6 points).
5
name:_______________________
student ID:_____________________
7. In two interrupted mating experiments, you obtain the data shown below for the time of entry.
All experiments used Hfr strains derived from the same original parent strain.
Hfr1
gal
arg
thr
val
met
5 min
8 min
15 min
20 min
30 min
A. Show the genetic map for each of these genes on the circular chromosome. Indicate the
location of each origin and the direction of transfer (5 points).
B. Please describe briefly how you would identify the gal and arg wild-type recombinants that
you see in part A of this question (3 points).
8. Here is the pedigree of a rare genetic disorder. Assume
that individuals who marry into the pedigree do not have the
mutation that produces the trait.
A. Name and describe the type of inheritance exhibited in
this pedigree (4 points).
B. What is the probability that the person indicated by the question mark will show the trait (3
points)?
6