MCQs in Microbiology: Miscellaneous Topics

1. Which of the following drug is used to treat fungal infections?
   a. erythromycin
   b. penicillin
   c. amphotericin B
   d. Quinine
   e. none of the above
2.  Pili/fimbrae are thin short appendages extruding from the cytoplasmic membrane of certain bacteria. These pili/fimbriae are involved in
   a. movement
   b. attachment
   c. DNA transfer
   d. a and b
   e. b and c
3. What organism is considered an index of fecal pollution of drinking water supplies?
   a. Rotavirus
   b. E. coli
   c. Salmonella spp.
   d. Hepatitis E virus
4. Protective mechanisms used by bacteria to survive in the host maybe
   a. capsules
   b. M protein
   c. various enzymes
   d. all of the above
5. Endotoxins are heat stable lipopolysaccharide-protein complexes that form the structural components of the cell wall of bacteria.
   Which of the following statement regarding endotoxin is correct?
   a. all have the same effect regardless of bacterial source
   b. are found in both gram-positive and gram-negative bacterial cell wall
   c. are part of the cell wall of gram-positive bacteria only
   d. none of the above statements are correct
6. Ethanol is one of the most commonly used disinfectants. Which concentration of ethanol is most effective for this purpose?
   a. 100%
   b. 70%
   c. 50%
   d. 30%
7. Which of the following are reservoirs for human infection?
   a. food and water
   b. humans
   c. animals
   d. all of the above
8.  A typical growth curve consists of FOUR phases. Which is the correct sequence?
   a. exponential, lag, stationary, death
   b. lag, exponential, stationary, death
   c. stationary, exponential, lag, death
   d. lag, stationary, exponential, death
9. Which of the following are true about viruses?
   a. they are not composed of cells
   b. as virions they cannot metabolize nutrients
   c. they alone cannot reproduce themselves
   d. they contain DNA or RNA
   e. all of the above
10. The correct sequence for the viral life cycle is:
    a. attachment, biosynthesis, penetration, maturation, release
    b. penetration, biosynthesis, attachment, maturation, release
    c. attachment, penetration, biosynthesis, maturation, release
    d. biosynthesis, attachment, penetration, maturation, release

Answer Keys for MCQs in Microbiology (1-10)

1. c. amphotericin B
2. e. b & c (Attachment and DNA transfer)
3. b. E. coli
4. d. all of the above
5. a. all have the same effect regardless of bacterial source
6. b. 70%
7. d. all of the above
8. b. lag, exponential, stationary, death
9. e. all of the above
10. c. attachment, penetration, biosynthesis, maturation, release