Portage Learning BIOD 171 Module 6 || with 100%
Errorless Answers.
Can viruses be classified as either prokaryotic or eukaryotic? correct answers No. Viruses are
neither prokaryotic nor eukaryotic.
What is an obligate intracellular parasite? correct answers Viruses cannot replicate unless inside
a living host cell. A virus depends on its living host to provide the framework to replicate.
What is a viral capsid? correct answers The capsid is a membrane-like protective structure that
contains the genetic material, similar to the nucleus of a eukaryotic cell.
What is the viral envelope, and what does the presence (or absence) of it tell you about the type
of virus? correct answers The viral envelope surrounds the viral capsid and serves as an
additional barrier to the external environment. The majority of animal viruses are enveloped
where as plant or bacteria infecting viruses are not.
What type of microscope would be used to study the shape of a viral capsid? correct answers
Due to its size (~30-150 nm) most viral capsids must be visualized via electron microscopy.
How does the viral envelope both aid in cell entry as well as hide it from being detected by the
immune system? correct answers It contains the proteins required for interaction with host cells.
As the envelope is derived from the host cell, this camouflages the virus and makes it appear
similar to the normal host cell.
What must happen before viral replication of its genome can occur? correct answers The genome
is replicated following attachment and entry
Describe the basic steps of the viral life cycle. correct answers 1. Attachment: Viral receptors
bind to host proteins on the surface of the cell.
2. Entry: The virus fuses with the host membrane and enters the cell
3. Uncoating: (where applicable) the viral capsid disassembles
4. Replication: The viral genome provides the 'blueprint' to make copies of itself
5. Exit: New viruses are produced and leave the cell
6. New infection: Newly produced viruses leave the host cell and go on to infect new cells. The
process outlined above now restarts.
What is a bacteriophage? correct answers A virus that infects bacteria
What structural aspects make bacteriophages distinct from viruses that infect either animals or
plants? correct answers They have an icosahedral capsid head and a helical tail.
Which viral replicative process results in the destruction of the host cell? correct answers The
lytic replication cycle
Errorless Answers.
Can viruses be classified as either prokaryotic or eukaryotic? correct answers No. Viruses are
neither prokaryotic nor eukaryotic.
What is an obligate intracellular parasite? correct answers Viruses cannot replicate unless inside
a living host cell. A virus depends on its living host to provide the framework to replicate.
What is a viral capsid? correct answers The capsid is a membrane-like protective structure that
contains the genetic material, similar to the nucleus of a eukaryotic cell.
What is the viral envelope, and what does the presence (or absence) of it tell you about the type
of virus? correct answers The viral envelope surrounds the viral capsid and serves as an
additional barrier to the external environment. The majority of animal viruses are enveloped
where as plant or bacteria infecting viruses are not.
What type of microscope would be used to study the shape of a viral capsid? correct answers
Due to its size (~30-150 nm) most viral capsids must be visualized via electron microscopy.
How does the viral envelope both aid in cell entry as well as hide it from being detected by the
immune system? correct answers It contains the proteins required for interaction with host cells.
As the envelope is derived from the host cell, this camouflages the virus and makes it appear
similar to the normal host cell.
What must happen before viral replication of its genome can occur? correct answers The genome
is replicated following attachment and entry
Describe the basic steps of the viral life cycle. correct answers 1. Attachment: Viral receptors
bind to host proteins on the surface of the cell.
2. Entry: The virus fuses with the host membrane and enters the cell
3. Uncoating: (where applicable) the viral capsid disassembles
4. Replication: The viral genome provides the 'blueprint' to make copies of itself
5. Exit: New viruses are produced and leave the cell
6. New infection: Newly produced viruses leave the host cell and go on to infect new cells. The
process outlined above now restarts.
What is a bacteriophage? correct answers A virus that infects bacteria
What structural aspects make bacteriophages distinct from viruses that infect either animals or
plants? correct answers They have an icosahedral capsid head and a helical tail.
Which viral replicative process results in the destruction of the host cell? correct answers The
lytic replication cycle
