BIO 3401 FINAL EXAM UPDATED ACTUAL QUESTIONS AND CORRECT ANSWERS

BIO 3401 FINAL EXAM UPDATED ACTUAL QUESTIONS
AND CORRECT ANSWERS

Question:
1. Which of the following is true of germ-free animal models? Select all answers that are correct.
a) Germ-free animals have altered intestinal size/shape.
b) Germ-free animals have improved resistance to pathogens like C. difficile
c) Two animals that can be raised germ-free are mice and pigs.
d) Germ-free animals are less susceptible to certain autoimmune disorders.
Answer:
a, c, d

Question:
2. In Nissle's World War I-era experiment, as described in lecture, which approaches were used? Select all
answers that are correct.
a) gnotobiotic animals
b) microscopy
c) human trial (probiotics)
d) liquid/solid culture
e) human trial (FMT)
f) human trial (prebiotics)
Answer:
c,d

Question:
3. The Great Plate Count Anomaly involved a discrepancy where microbial cell counts obtained by
[________] were much lower than those obtained by [________] .
Answer:
culture, microscopy

Question:
4. An alternative way to study these microbes is via [________] . This third method has allowed scientists
to gain much more information about the individual microbes of a community in a cost-effective way,
regardless of whether or not they can be studied using the first method.
Answer:
sequencing

Question:
5. Which of the following qualities make 16S rRNA a good marker gene for prokaryotes?
a) It is a non-protein-coding gene.
b) It forms part of the ribosome.
c) It forms secondary structures like stems and loops.
d) It is universally present and has both highly conserved and variable regions.
e) It can be horizontally transferred.
Answer:
d

, Question:
6. Assume I am doing a case-control study. If I split all my samples into three age bands (18-35, 36-50, and
51-80), then compare only the cases and controls in the same age band, what strategy have I used for
dealing with potential confounders?
a) stratification
b) matching
c) randomization
Answer:
a

Question:
7. Place the experimental techniques in order of their development, from earliest to latest.
Answer:
1. microbiome transplant (veterinary)
2. microscopy
3. liquid/solid culture
4. germ-free animals
5. high-throughput sequencing

Question:
8. Match hypothesis to the most appropriate experimental design you could use to investigate it. People
with psoriasis tend to have higher levels of Citrobacter in their gut microbiomes.
Answer:
case-control study

Question:
9. Match hypothesis to the most appropriate experimental design you could use to investigate it. By giving
Citrobacter from sick individuals to healthy individuals, we can worsen symptoms of psoriasis.
Answer:
mouse model

Question:
10. Match hypothesis to the most appropriate experimental design you could use to investigate it. People
who have high levels of Citrobacter are more likely to go on to develop psoriasis.
Answer:
cohort study

Question:
11. Match hypothesis to the most appropriate experimental design you could use to investigate it. Gut
microbes from a healthy individual can help to treat psoriasis.
Answer:
randomized controlled trial (FMT)

Question:
12. Match hypothesis to the most appropriate experimental design you could use to investigate it. Increased
consumption of the fiber inulin can help treat psoriasis by changing the gut microbiome.