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Biology 120 Lab Exam 2 Review
Student Learning Services and Biology 120 Peer Mentors
Sunday, March 26th, 2017
6:00 pm
Arts 263
Important note: This review was written by your Biology Peer Mentors (not the lab instructors)!
It is designed to help you test yourself on topics and concepts covered in lab and should not in
any way be considered a “preview” of the actual exam.
You are encouraged to attempt to complete this review without the lab
manual, text book, your notes, or the internet. The peer mentors are
available while you are working to help you with any questions that
cause you difficulties.
NOTE: This version of the review has been revised.
Revision(s):
 Question 7e) had a repeated statement removed.
 Question 17 has had an answer changed for clarification
 The gel in question 18 has been changed to give a clear answer
and better reflect lab expectations.
Structured Study Session information
Mondays 2:00-3:20pm – Room 104 in the Arts Building (Mars)
Tuesdays 8:30am-9:50am – Room 213 in the Arts Library (Dakoda)
Tuesdays 5:30-6:50pm – Room G3 in the Murray Library (Maryam)
Wednesdays 11:30am-12:50pm – Room 211 in the Arts Building (Alexa)
Thursdays 11:30am-12:50pm – Room 124 in the Biology Building (Hayley)
Thursdays 3:00-4:20pm – Room 104 in the Arts Building (Tara)
Spot Test
1.
No, it’s unreplicated
2.
AB, Ab, aB, ab
3.
Prophase I
4.
Tetrad/bivalent
5.
No, they are not homologous
6.
gametophyte
7.
archegonia
8.
antheridia
9.
rhizoids
10.
Missing an X chromosome
11.
Turner syndrome
12.
-short stature
-nonfunctioning ovaries (infertility)
-webbed neck
-wide chest
13.
Gel electrophoresis
14.
John
15.
Dad 3: He provides all the bands the child has but the mother does not
Short Answer
1. Fill in the Blanks:
a) Plants have a complex life cycle called an __alternation___ __of__
______generation___, meaning that they have distinct multicellular haploid and
diploid stages.
b) _____Sporocytes___ undergo meiosis to form haploid cells called spores.
c) Crossing over occurs in ____Prophase I___ stage of meiosis.
d) In the fern life cycle the species in a haploid during the ____gametophyte_____
stage, whereas the species is diploid during the ____sporophyte___ stage.
e) In animals meiosis only occurs in the
testis
or
ovaries , and results in
the production of haploid gametes ( _sperm__ or eggs __)
Questions and answers for the lab exam review will be posted after the session at: http://library.usask.ca/sss
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2. Harry Potter is in Herbology class and is studying mandrakes. A grumpy looking (R)
mandrake is dominant to happy looking (r) mandrakes. The mandrakes in his care, which
are all offspring of the same cross, are 50% homozygous dominant and 50%
heterozygous. What were the genotypes of the parents of these mandrakes?
RR and Rr
3. During Potions, Harry learns that about 90% of wizards and witches perceive a sweet
taste from the Felix Felicis potion. The ability to taste this results from a dominant allele
(T). He also learns that in very rare cases drinking the potion causes people to turn
purple, the ability being called “purple-turners”. Being a purple-turner is a single locus
trait that is recessive (a) to normal pigment. A normally pigmented woman who cannot
taste the sweetness of Felix Felicis has a father who is a purple-turner non-taster. She
marries a homozygous, normally pigmented man who is a taster but who has a mother
that does not taste sweetness.
a) List all possible genotypes resulting from this cross.
AATt, AAtt, AaTt, Aatt
b) What proportion of the children will be purple-turners? ___0__
c) What proportion of the children will be non-tasters? __ ½ ___
4. During the class Care of Magical Creature, Hagrid is showing off Hippogriffs. The genes
that code for Hippogriff fur colour and nail sharpness are linked, 23.4 mu apart.
Brown fur (B) is dominant to white (b) and sharp nails (G) are dominant to dull (g).
Buckbeak’s mother had white fur and sharp nails, while his father had brown fur and
dull nails.
a) If Buckbeak who was brown fur and sharp nails mates with Fleetwing who has
white fur and dull nails what will be the phenotypic and genotypic frequencies of
their offspring?
0.117 Brown Sharp, 0.383 Brown Dull, 0.383 White Sharp, 0.117 White Dull
0.117 BbGg, 0.383 Bbgg, 0.383 bbGg, 0.117 bbgg
b) Draw a cell from Buckbeak in Telophase II of Meiosis. Assume no crossing over
has occurred.
5. Squibness in wizarding families results in a complete lack of magical ability. It is caused
by the recessive allele (t) of an X-linked gene. Amanda, a carrier female for squibness
marries Jason, a normally magical male.
Questions and answers for the lab exam review will be posted after the session at: http://library.usask.ca/sss
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a) Draw a Punnet square for this cross.
XT
b) If they have 2 sons and 4 daughters:
i. How many of the male offspring can
Y
XT XTXT XTY
Xt XTXt
XtY
be expected to be
Squibs? ___1____
ii.
How many of the offspring can be expected to have normal magical
abilities? ___5___
iii.
How many of the female offspring can be expected to be carriers? __2___
iv.
How many of the daughters can be expected to be magical? __4____
6. In kneazles, magical creatures that resemble cats, the allele for black fur (B) is dominant
to the allele for beige fur (b), and the allele for a puffy-ended tail (T) is dominant to the
allele for a pointed-ended tail (t). The gene for fur colour is 9.6 map units from the gene
for tail type.
a) Draw a Punnett square to illustrate the cross between Mrs Paws, a kneazle with
beige fur and a pointed-ended tail and Crookshanks, a kneazle who had black fur
and a puffy-ended tail (both of Crookshank’s parents were homozygous for both
traits; his mom had black fur and a puffy-ended tail, and his dad had beige fur
with a pointed-ended tail).
bt
Parental
BT
BbTt
45.2
Recomb
Bt
Bbtt
4.8
Recomb
bT
bbTt
4.8
Parental
bt
bbtt
45.2
b) What is the expected genotypic ratio of their offspring?
9.42 BbTt : 1 Bbtt : 1 bbTt : 9.42 bbtt
7. Instead of studying for his upcoming final exams, Harry Potter procrastinates and
instead studies house elf genetics (“elfnetics”) as they prepare Easter dinner at the
Hogwarts kitchen. In particular, he observes height and ear length, traits dependent on
genes that he knows are autosomal. In the P generation, the female house elf is short
and has short ears and the male house elf is tall with long ears. All of the house elves in
the F1 generation are short and have long ears. Use “A” to indicate height, and “B” for
ear length.
a) The genotypes of the house-elves in the P generation are:
Female: __ AAbb ____
Male: _ aaBB ____
b) The genotype of the house-elves in the F1 generation is: __ AaBb __
c) An F1 female crosses with a true-breeding tall, short ears male.
This male’s genotype is: ____ aabb ____
Questions and answers for the lab exam review will be posted after the session at: http://library.usask.ca/sss
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d) Harry Potter counts 16 offspring in the F2 generation (from the parents of
question c). List the number, phenotypes, and genotypes he would expect if
height and ear length were linked and no recombination occurred.
8 Aabb (Short and Short), 8 aaBb (Tall and Long)
e) When he counts the F2 generation in the Hogwarts kitchen, he found the
following results:
1 short, long eared
7 tall, long eared
7 short, short eared
1 tall, short eared
Calculate the distance, in map units, between the genes for height and ear length.
12.5 map units
8. The following pedigree illustrates the inheritance of Spontaneous Expelliarmus in a
population.
Use ‘E’ to represent the gene responsible.
A
Normal female
Normal male
B
C
Female with trait
D
a) What is most likely the mode of inheritance?
Autosomal Recessive
b) What is the genotype of A? ____ Ee________
c) What is the genotype of D? ____ ee_______
d) If individual B and C have a son what is the chance that he will have spontaneous
expelliarmus?
50%
Questions and answers for the lab exam review will be posted after the session at: http://library.usask.ca/sss
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9. The following pedigree illustrates the inheritance of pterydactyl (development of bat
wings) in cats.
Use ‘P’ to represent the gene responsible.
Normal female
Normal male
Female with trait
Male with trait
Autosomal Dominant
a) What is the most likely mode of inheritance for this trait? _________________
b) Give the genotypes of the following individuals. Use the letter “P” for this trait.
6 _____________
Pp
c)
7 ______________
Pp
8 ______________
pp
If Individuals 6 and 7 have another daughter, what are the chances that she will
75%
be affected? ______
You are working as a forensic scientist for the Biology 120 Crime Scene Unit. You are called
to a crime scene in the biology building. At the crime scene, you discover blood splatter on
the mirror, hair fibres located in the sink, and urine samples along the wall.
10. What is the first step after you have collected cells from the scene?
DNA Extraction, specifically addition of cell lysis or detergent.
11.
a) What component of blood, urine and hair fibres can you collect DNA from?
The nucleus
b) Which of the three (blood, urine, or hair fibres) would be the best sample
choice? Explain.
Urine OR Blood
12. After extracting the DNA from your sample, you put it the thermal cycler. What other
ingredients should you add?
DNTP’s, DNA (taq) Polymerase, and Primers
13.
a) Name the process that utilizes a thermal cycler.
PCR- Polymerase Chain Reaction
b) What are the steps in this process?
i. DNA denaturation
ii. Anneal primers
iii. Extend primers
Questions and answers for the lab exam review will be posted after the session at: http://library.usask.ca/sss
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14. What must you add to a DNA sample in the first step of Restriction Fragment Analysis?
Restriction Enzyme (EcoR1, BAMH1)
15. Your sample is prepared, it is now time to analyze the DNA sample. Name the device
that you will use to load the samples into the wells of a gel.
Micropipette
16. What makes up the gel used in gel electrophoresis?
Agarose gel
17. Which of the following combinations work for analyzing DNA samples with a gel?
a) Infrared light and Fast Blast
b) White Light and Methylene Blue
c) UV light and Methylene Blue
d) UV Light and Ethidium Bromide
18. You have successfully loaded your sample and run the gel. Based on the results below,
who is the murderer?
Ladder Crime Scene Victim
Suspect 1 Suspect 2
Suspect 2
19. Name three uses for modern biotechnology.
i. ______________________________________________
ii. ______________________________________________
iii. ______________________________________________
20. What is recombinant DNA?
A single DNA molecule with DNA from two different organisms
Questions and answers for the lab exam review will be posted after the session at: http://library.usask.ca/sss
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