Module 6 Flashcards
(43 cards)
True or False. Because the genome is contained within an enclosed space (much like the nucleus of a cell), viruses are classified as eukaryotic.
F
Describe the two basic components of a virus.
- Genomic material (DNA and RNA)
- Capsid (membrane-like structure that contains genetic material)
The envelope surrounds the _________ of some viruses.
Capsid
True or False. You would expect to see a viral envelope on a virus infecting a plant cell.
F
Rank the following viruses based on their size from largest to smallest:
Paramyxovirus
Poliovirus
Smallpox virus
smallpox
>paramyxovirus
>polio
SPP
True or False: Highly infectious viruses undergo genome replication prior to viral attachment and entry.
F
Place the following viral life cycle steps in order beginning with viral attachment and provide a description of each step.
Uncoating:
Release:
Replication:
Attachment:
Entry:
New infection:
- Attachment: the virus attaches the host cell through proteins on the host cell.
- Entry: the virus fuses with the host cell’s membrane and enters the cell.
- Uncoating: the capsid is disassembled
- Replication: Using genomic material from the virus, the virus replicates within the host cell.
- Release: new virus cells exit the host cell and are released.
- New Infection: the process continues resulting in an infection.
A virus that infects bacteria is called a [answer1] and contains a [answer2] -sided polygon capsid.
- Bacteriophage
- 20
True or False. Structurally, bacteriophages are distinct from viruses that infect plant or animal cells.
T
Identify the following components of a bacteriophage.
- capsid
- collar
- tail
- base plate
- tail fibers
Describe the main differences between lytic and temperate phages.
In lytic phages, replication continues to occur until the host cell dies. In temperate phages, replication and cell death do not occur.
Based on the following image, would you expect the viral titer to be high or low? Why?
Turbidity and Virus Levels:
High turbidity: Lots of bacteria, so fewer viruses.
Low turbidity: Fewer bacteria, so more viruses.
Mnemonic: “High turbidity, fewer viruses; low turbidity, more viruses.”
Which of the following can be spread via airborne particles:
measles
mumps
rubella
A and B
All of the above
All of the above
True or False. A patient infected with rubella is only considered infectious when the trademark rash is visible.
F
A patient diagnosed with German measles may additionally experience what disease? Select all that apply.
Conjunctivitis and Influenza-like symptoms.
Which of the following diseases does a linear, single-stranded RNA virus cause?
Measles
Mumps
Rubella
B and C
All of the above
All of the above
What disease is best characterized by painful swelling of the paratoid?
Mumps
Describe two ways chickenpox can be spread.
Chickenpox is highly contagious and can be transmitted (1) through both air-borne droplets (sneezing/coughs) or via (2) direct contact with the blisters of an infected individual.
True or False. The development of shingles is most often seen in an older adult population (> 60 years old).
T
True or False. Unlike chickenpox, the blisters that appear with shingles are localized and limited to small areas.
T
A person who has neither previously had chickenpox nor been administered the VZV vaccine is exposed to someone with an active VZV (shingles) outbreak and becomes infected. Explain why (or why not) the person will only develop shingles.
The infected individual will not develop shingles, but will develop chickenpox. Unvaccinated and unexposed individuals must first develop chickenpox, as shingles is the reactivation of the dormant VZV virus from the chickenpox infection.
What linear, double-stranded, enveloped DNA virus is the first virus (as of Oct. 26, 1977) to be officially declared eradicated?
Smallpox
What small (~30nm) single-stranded, non-enveloped RNA virus causes temporary or permanent paralysis by infiltrating (infecting) motor neurons within the spinal cord, brain stem, or motor cortex?
Polio
By whom and where was the first polio vaccine developed?
Jonas Salk; University of Pittsburg in 1955
