Week 2: Weekly Quiz

Question 1

All of the following are types of Cytopathic Effects (CPE) EXCEPT:

Question options:

Cells detaching from plates

All of the above

Cell rounding

None of the above

Syncytium formation

Answer 1

None of the Above

Question 2

You are a health-care provider who is treating a patient suspected of having SARS-CoV-2. You have just received their results from a COVID-19 rapid serology antibody test. The image is below. C = Control ; G = IgG ; M = IgM

What do these results mean?

Question options:

Test is valid ; Person is COVID-19 Positive with IgM and IgG antibodies

Test is valid ; Person is COVID-19 negative

Test is invalid ; Person is COVID-19 Positive with IgG antibodies

Test is invalid ; Person is COVID-19 Positive with IgM

Test is valid ; Person is COVID-19 Positive with IgG antibodies

Test is valid ; Person is COVID-19 Positive with IgM antibodies

Answer 2

Test is valid ; Person is COVID-19 Positive with IgM antibodies

Question 3

a. You determine that a total of 23 plaques are present in the 10-5 well. Calculate the concentration of virus in the original sample and express your answer in PFU / ml AND in scientific notation (i.e. 7.1 x 10 PFU/ml). Show your math for full credit (1 pt.)
b. ) Briefly describe what differentiates plaque assays from other methods to measure viruses. (1 pt.)

Answer 3

a. 2.3x10^7 PFU/mL

b.

Question 4

A cell that is susceptible may not necessarily be permissive to viral reproduction.

Question options:
True
False

Answer 4

True

Question 5

Calculate the MOI if you have a virus titer of 2 x 107 PFU/ml and want to infect 4 x 106 cells. Show your math and express your answer in scientific notation for full credit (1 pt.)

b.) Calculate the number of cells in the culture that will receive 1 virus particle. Round your answer to the nearest whole number. Show your math for full credit (1 pt.)

Answer 5

a. MOI = 2 x 107 PFU/ml / 4,000,000 cells = 5
b. P(1) = me^-m = 5 x e^(-5) = .0336

.0336 x 4 x 106 = 134758 = 1.3 x 10^5

Question 6

You are a researcher trying to determine the size/structure of a novel virus. What type of assay would best suit your needs?

Question options:

ELISA

Light microscopy: Live-cell imaging

Plaque Assay

RT-PCR

Electron Microscopy

Answer 6

?