PBIO 3300/5300-Spring 2017
Practice Final Exam (100 points)
NAME____________________________
There are three parts to this practice final exam, just like the real final exam (i.e., I. General
genetics knowledge, II. Multiple choice, and III. Short answer/Genetics problems). Good luck!
I. General genetics knowledge-20 points (1 points/question)
1. What two genetic contributions did Barbara McClintock make and what organism did she use?
2. Define chromatin, euchromatin and heterochromatin.
3. Define forward and reverse genetics.
4. What are allelic mutants?
5. What contribution did Matthew Meselson and Frank Stahl make to genetics?
6. What contribution did Alfred Hershey and Martha Chase make to genetics?
7. What is DICER?
8. What is a Shine-Dalgarno sequence and where is it found?
9. What is an enhancer?
10. What is epigenetics?
11. What is a synonymous mutation?
12. What is a translocation?
II. Multiple Choice (select the best answer and answer only 20 questions)-20 points
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1. A/a indicates which of the following?
a. heterozygous alleles b. homozygous alleles c. A and a are linked genes d. A is on one
homolog and a is on the other homolog e. a and d.
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2. A/a ; B/b indicates which of the following?
a. A and B are linked genes b. A and B are not linked genes c. AB are arranged in cis d. AB
are arranged in trans e. linkage cannot be determined without more information
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3. In chickens, the dominant allele Cr produces the creeper phenotype (having extremely short
legs). However, the creeper allele is lethal in the homozygous condition. If two creepers are
mated, what proportion of the living progeny will be creepers?
a. 1/4 b. 1/3 c. 1/2 d. 2/3 e. 3/4
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4. Which of the following is synthesized 3’ to 5’?
a. the leading strand b. the lagging strand c. mRNA d. a and c e. none of these
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5. What kind of mutation introduces a premature stop codon into a gene?
a. Nonsense b. Silent c. Missense d. Frameshift e. Inversion
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6. An activation domain and a DNA binding domain are found in which of the following?
a. enhancer b. TFIIB c. RNA polymerase d. transcriptional activators e. insulators
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7. Which of the following are missing in a retrotransposon?
a. LTRs b. gag c. pol d. env e. c and d
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8. Which of the following mutations likely results in frameshifts?
a. synonomous b. missense c. insertions d. deletions e. c and d
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9. Which of the following is not involved with an Ames test?
a. PCR b. yeast c. mice d. liver e. a potential mutagenic compound
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10. MutH detects the original methylated DNA in which of the following repair mechanisms?
a. photo reactivation b. mismatch c. base excision d. transcription coupled e. photolyase
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11. Colchicine is used to produce which of the following?
a. Haploids b. Aneuploids c. Translocations d. Polyploids e. Inversions
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12.A wild-type chromosome can be represented as ABC * DEFGH and from this a chromosomal
aberration arises that can be represented ABC * DEGFH ( * = centromere). This is known as a:
a. deletion b. translocation c. duplication d. pericentric inversion e. paracentric inversion
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13. Which of the following is least likely to involve QTLs?
a. white or blue flower color b. height c. intelligence d. dog body size e. fruit yield
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14. In a human population, the genotype frequencies at one locus are 0.5 AA, 0.4 Aa, and 0.1 aa.
The frequency of the A allele is:
a. 0.20 b. 0.32 c. 0.50 d. 0.70 e. 0.90
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15. Which statement is true regarding broad heritability and continuous variation in quantitative
traits?
a. Heritability measures the degree to which genes determine phenotype b. As the number of
gene loci that affect a trait increases, the proportion of extreme version of the trait also increases
c. The total variance used to calculate heritability measures all the variance in a population
d. A heritability value of 0.8% of the total variance is due to differences in the environment
e. A low heritability score means that genes are less influential than environment in determining
phenotypic variation
III. Short answer. (5 points/question).
1. Draw a linkage map consistent with the following recombination frequencies:
A-B 15%, A-C 39%, B-C 24%, B-D 9%, A-D 24%, C-D 15%
2. Discuss the model of how flower development is controlled in Arabidopsis and explain the
role that genetic mutants had in elucidating this model.
3. How can enhancers work over such great distances to activate eukaryotic genes? How can
the action of an enhancer be limited to only one gene if it occurs between two adjacent
genes?
4. Design a microarray experiment to elucidate genes that are involved with drought stress in
Arabidopsis. Explain how you would conduct the experiment and interpret the results.
5. Human transposable elements exist, but no longer appear to be moving around very much in
the human genome. Discuss the two most likely reasons for this observation.
6. Diagram and explain how a translocation could lead to cancer.
7. Is the repair of DNA mutations important to organisms? What mechanisms do organisms have
to repair DNA damage?
8. Complex traits show variance around some mean value. Discuss what causes such variance
and how it can be examined in human populations.
9. Explain how malaria is related to evolution and natural selection.
10. What is CRISPR-CAS9 and how does it work?
11. Are genetic mutations a bad or good thing? Discuss.
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