Multiple-choice questions

Some subjects have exams with short or multiple-choice questions [MCQs].

For instance, biology and other sciences are often tested in this way. Their main purpose is to teach factual knowledge.

Beware! In MCQ exams, wrong answers may carry penalty marks. This is so you can't pass just by guesswork.

This means you have to be careful how you answer. It also means you have to read the questions carefully.

Notice that the sample questions which follow become increasingly complex.

The questions only require a choice, but careful thought is required.

You need to read the instruction terms very carefully.

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First Year INTRODUCTORY VIROLOGY

Section A (20 mins)

Answer all questions

In questions 1 to 6 select the ONE most suitable answer from the options provided.

1. The infectivity of an animal virus suspension may be quantitatively measured by

A. protein assay
B. colony count
C. electron microscopy
D. plaque assay
2. Animal virus infectivity is destroyed by

A. ribonuclease
B. pH 6.8
C. a temperature of 4 degrees C
D. oxidising agents
3. Animal virus particles enter susceptible cells by

A. osmosis
B. endocytosis
C. electrophoresis
D. plasmapheresis
.........

In questions 7 to 13 select the ONE INCORRECT response from the options provided.

7. Some plant viruses can be transmitted by species of

A. aphids
B. leaf-hoppers
C. bees
D. fungi
8. A bacterium carrying a prophage

A. has been infected by a temperate phage
B. may divide to give daughter bacteria
C. may enter the lytic cycle if stressed by UV radiation
D. cannot transcribe RNA
...........

In questions 14 to 20 answer

A. if only (i) (ii) and (iii) are correct
B. if only (i) and (iii) are correct
C. if only (ii) and (iv) are correct
D. if only (iv) is correct
E. if all are correct

14. Which of the following methods of assaying plant viruses gives a measure of the concentration of infective virus present in a sample?

(i) dilution end-point
(ii) electron microscopy
(iii) local lesion assay
(iv) UV assay

15. A plant virus may cause a systemic infection if the host plant is

(i) susceptible
(ii) resistant
(iii) tolerant
(iv) immune