BIOD 171: MICROBIOLOGY LECTURE EXAM
Q&A
1. A virus that infects bacteria is called a and contains a -side polygon
capsid.
Bacteriophage; 20-sided
2. True or False. Structurally, bacteriophages are similar to viruses that infect
animals.
False. Bacteriophages have a distinct composition and structure.
3. Identify the following components of a bacteriophage.
1-Capsid (or
,BIOD 171: MICROBIOLOGY LECTURE EXAM
Q&A
Head) 2-
Collar
3- Tail (sheath)
,BIOD 171: MICROBIOLOGY LECTURE EXAM
Q&A
4- Base
plate 5-
Tail
fibers
1. Describe the main differences between lytic and temperate phages.
Lytic bacteriophages replicate within the host bacteria until it ruptures, whereas
temporate (or lysogenic) phages primarily exist in a non-replicative state that
does not kill the host cell.
Lytic phages replicate all viral proteins needed for the assembly of new virus
particles whereas lysogenic phage genomes are integrated into the host genome
but production of viral proteins is suppressed.
2. Based on the following image, would you expect the viral titer to be high or
low? Why?
, BIOD 171: MICROBIOLOGY LECTURE EXAM
Q&A
Low. As turbidity is a function of the number of intact bacterial cells present in
the media, the amount of virus contained within the above tube must be low. As
the lytic cycle continues more and more bacterial cells will be destroyed,
effectively clearing the media.
1. Which of the following cannot be spread via airborne particles:
A. Measles
B. Mumps
C. Rubella
D. A and B
E. None of the above
Q&A
1. A virus that infects bacteria is called a and contains a -side polygon
capsid.
Bacteriophage; 20-sided
2. True or False. Structurally, bacteriophages are similar to viruses that infect
animals.
False. Bacteriophages have a distinct composition and structure.
3. Identify the following components of a bacteriophage.
1-Capsid (or
,BIOD 171: MICROBIOLOGY LECTURE EXAM
Q&A
Head) 2-
Collar
3- Tail (sheath)
,BIOD 171: MICROBIOLOGY LECTURE EXAM
Q&A
4- Base
plate 5-
Tail
fibers
1. Describe the main differences between lytic and temperate phages.
Lytic bacteriophages replicate within the host bacteria until it ruptures, whereas
temporate (or lysogenic) phages primarily exist in a non-replicative state that
does not kill the host cell.
Lytic phages replicate all viral proteins needed for the assembly of new virus
particles whereas lysogenic phage genomes are integrated into the host genome
but production of viral proteins is suppressed.
2. Based on the following image, would you expect the viral titer to be high or
low? Why?
, BIOD 171: MICROBIOLOGY LECTURE EXAM
Q&A
Low. As turbidity is a function of the number of intact bacterial cells present in
the media, the amount of virus contained within the above tube must be low. As
the lytic cycle continues more and more bacterial cells will be destroyed,
effectively clearing the media.
1. Which of the following cannot be spread via airborne particles:
A. Measles
B. Mumps
C. Rubella
D. A and B
E. None of the above
