Explain what is meant by viral host range. Also address what factors affect a virus’ host range, and what is meant by tissue tropism.

1. How did Edward Jenner test and create the first vaccine? Describe the steps of this
process from observation to hypothesis to testing and finally, establishment of a theory.
(100 words or less) (The word count on all the short answer questions is a SUGGESTED
word count. It is okay if you go over the word count. You will not lose points, but it
easier for me to grade if you stay within the word count.)
2. Explain what is meant by viral host range. Also address what factors affect a virus’ host
range, and what is meant by tissue tropism.
3. In your own words, describe the theory of endosymbiosis. (50 words or less).
4. Consider the following double-stranded DNA strands:
A)5′ ATG TTC ACA 3′
3′ TAC AAG TGT 5′
B)
5′ CCG GAG CTC 3′
3′ GGC CTC GAG 5′
Which DNA strand would require more energy to break the hydrogen bonds between its
bases? A or B? Why? (50 words or less).
5. Please transcribe the DNA sequence seen below into its complementary RNA sequence:
GCA CCA TTG GCC ATG TGG ACC ACG GCA AGA
Then using the RNA sequence that you transcribed, please translate it into its
corresponding amino acid sequence. Please write the amino acid corresponding to each
codon in the sequence. Use the amino acid chart to guide you.
6. Please describe how DNA replication occurs on the leading strand vs. the lagging strand
of DNA. Please be sure to mention how are these processes similar? How are they
different? (150 words or less).
7. Explain what is meant by the following diagram. (50 words or less). (You will need to
view the exam on Canvas to see the diagram).
8. Describe the different ways that a bacteria can acquire drug resistance genes.
(Remember that we discussed several various ways in class that this can occur, not just
one! Think about the case study!) (150 words or less)
9. Compare and contrast chickenpox and shingles. What is the name of the virus that
causes these diseases? How are chickenpox and shingles similar? How are they
different? How does chickenpox occur and how does shingles occur? Also explain why
someone who once had chickenpox would require a shingles vaccine in older age. (150
words or less)
10. What are the 3 means of horizontal gene transfer in bacteria? Please list them AND
describe them. (Be sure to describe them! Not only mention them