Week 10 Application Questions

Question 1

Part A: DNA replication, transcription and gene structure

1. Draw a DNA double helix in the process of replication in 2 colours. Start with both strands the same colour, then draw in the new strands with a second colour.

In this way, illustrate and explain semi-conservative replication. Add the location of some enzymes, label the leading and lagging strand

Question 2

Part A: DNA replication, transcription and gene structure

2. Explain why the definition of a gene does not include the word protein.

What other final products could come from a gene?.

Question 3

Part A: DNA replication, transcription and gene structure

3. What is the central dogma of molecular biology? Make a flow chart illustrating the flow of information in a cell.

Question 4

Part A: DNA replication, transcription and gene structure

4. One of the scientific breakthroughs in the wake of the COVID-19 pandemic is the development of mRNA vaccines (e.g. BioNTech/Pfizer and Moderna), that contain the mRNA for a subunit of the spike protein for the SARS- CoV-2 virus.

Your friend is afraid that when being injected with viral mRNA, it will take over and change their own DNA.

Based on the central dogma and the flow of information in a cell should they be concerned?

What would you tell them?

Question 5

Part B: Translation and the genetic code

5. What are the advantages to the cell of having one tRNA able to read multiple codons? (wobble)

Question 6

Part B: Translation and the genetic code

6. One of the scientific breakthroughs in the wake of the COVID-19 pandemic is the development of mRNA vaccines (e.g. BioNTech/Pfizer and Moderna), that contain the mRNA for a subunit of the spike protein for the SARS- CoV-2 virus.

a. Based on the content of this topic name and describe the process necessary for the vaccine to result in the production of the spike protein in a (human) cell.

Question 7

Part B: Translation and the genetic code

6. One of the scientific breakthroughs in the wake of the COVID-19 pandemic is the development of mRNA vaccines (e.g. BioNTech/Pfizer and Moderna), that contain the mRNA for a subunit of the spike protein for the SARS- CoV-2 virus.

b. Do you think a dose needs to contain a lot of mRNA because otherwise it might be “used up” and not produce enough proteins for a response?

Question 8

Part B: Translation and the genetic code

7. Tetracyclines (a class of antibiotics) prevent the binding of aminoacyl tRNAs

a. What site within the ribosome do you think they bind at? (APE)

Question 9

Part B: Translation and the genetic code

7. Tetracyclines (a class of antibiotics) prevent the binding of aminoacyl tRNAs

b. What stage(s) of translation would tetracyclines affect?

Question 10

Part B: Translation and the genetic code

7. Tetracyclines (a class of antibiotics) prevent the binding of aminoacyl tRNAs

c. Based on their target, would you expect tetracyclines to kill or merely weaken a cell?

Question 11

Part B: Translation and the genetic code

8. Fig. 12.19 shows translation of a secreted protein.

What steps would be different if the protein being produced functioned in the membrane instead?

Question 12

Part B: Translation and the genetic code

9. Which would be more serious, a deletion of a single base pair in an exon, or a deletion of a set of three bases in an exon?

Question 13

Part B: Translation and the genetic code

10. Using a codon table translate the following transcript, using the one letter code for amino acids (assume it’s from the middle of a sequence without disrupting the reading frame):

5’-CAUGCGCCCCCAUAU-3