True or False: Because the genome is contained within an enclosed space, (much like the nu-
cleus of a cell) viruses are classified as eukaryotic - ANSWER False. Viruses are neither eu-
karyotic nor prokaryotic
Describe the two basic components of a virus (short answer) - ANSWER A virus has 1. ge-
nomic material comprised of either DNA or RNA and 2. a capsid, a membrane-like protective
structure that contains the genetic material, similar to the nucleus of a eukaryotic cell
The _____ surrounds the capsid of some viruses - ANSWER Envelope
The envelope surrounds the _____ of some viruses - ANSWER Capsid
True or False: You would expect to see a viral envelope on a virus infecting a plant cell - AN-
SWER False. The overwhelming majority of animal viruses are enveloped whereas the
majority of plant or bacteria-infecting viruses are not
True or False: You would expect to see a viral envelope on a virus infecting a bacterial cell -
ANSWER False: Not all the viruses have envelopes
Rank the following viruses based on their size from largest to smallest: orthomyxovirus, po-
liovirus, variolavirus - ANSWER Variolavirus>Orthomyxovirus>Poliovirus
Rank the following viruses based on their size from largest to smallest:Paramyxovirus, Po-
liovirus, Smallpox virus - ANSWER Smallpox>Paramyxovirus>Poliovirus
1
, True or False: Viral replication occurs after it attaches and enters the host cell - ANSWER
True. The viral genome is never replicated before attachment and entry
True or False: Highly infectious viruses undergo genome replication prior to viral attachment
and entry. - ANSWER False. The viral genome is never replicated before attachment and
entry regardless of its level of infectivity.
Place the following viral life cycle steps in order beginning with viral attachment and provide
a description of each step (short answer) - ANSWER Uncoating: the viral capsid disassem-
bles
Release: New virus particles are produced and leave the cell
Replication: the viral genome is the 'blueprint' to make copies of itself
Attachment: viral receptors bind to host proteins on the surface of the cell
Entry: the virus fuses with the host membrane and enters the cell
New Infection: newly produced viruses that left the host cell now go on to infect new cells
A virus that infects bacteria is called a _____ and contains a _____ -side polygon capsid (fill
in the blank) - ANSWER Bacteriophage; 20-sided
True or False: Structurally bacteriophages are similar to viruses that infect animals - AN-
SWER False. Bacteriophages have a distinct composition and structure
True or False. Structurally, bacteriophages are distinct from viruses that infect plant or ani-
mal cells. - ANSWER True. Bacteriophages are structurally distinct from viruses that infect
plant and animals cells.
Identify the following components of a bacteriophage (picture) - ANSWER 1. Capsid
2. Collar
3. Tail
4. Base
2
cleus of a cell) viruses are classified as eukaryotic - ANSWER False. Viruses are neither eu-
karyotic nor prokaryotic
Describe the two basic components of a virus (short answer) - ANSWER A virus has 1. ge-
nomic material comprised of either DNA or RNA and 2. a capsid, a membrane-like protective
structure that contains the genetic material, similar to the nucleus of a eukaryotic cell
The _____ surrounds the capsid of some viruses - ANSWER Envelope
The envelope surrounds the _____ of some viruses - ANSWER Capsid
True or False: You would expect to see a viral envelope on a virus infecting a plant cell - AN-
SWER False. The overwhelming majority of animal viruses are enveloped whereas the
majority of plant or bacteria-infecting viruses are not
True or False: You would expect to see a viral envelope on a virus infecting a bacterial cell -
ANSWER False: Not all the viruses have envelopes
Rank the following viruses based on their size from largest to smallest: orthomyxovirus, po-
liovirus, variolavirus - ANSWER Variolavirus>Orthomyxovirus>Poliovirus
Rank the following viruses based on their size from largest to smallest:Paramyxovirus, Po-
liovirus, Smallpox virus - ANSWER Smallpox>Paramyxovirus>Poliovirus
1
, True or False: Viral replication occurs after it attaches and enters the host cell - ANSWER
True. The viral genome is never replicated before attachment and entry
True or False: Highly infectious viruses undergo genome replication prior to viral attachment
and entry. - ANSWER False. The viral genome is never replicated before attachment and
entry regardless of its level of infectivity.
Place the following viral life cycle steps in order beginning with viral attachment and provide
a description of each step (short answer) - ANSWER Uncoating: the viral capsid disassem-
bles
Release: New virus particles are produced and leave the cell
Replication: the viral genome is the 'blueprint' to make copies of itself
Attachment: viral receptors bind to host proteins on the surface of the cell
Entry: the virus fuses with the host membrane and enters the cell
New Infection: newly produced viruses that left the host cell now go on to infect new cells
A virus that infects bacteria is called a _____ and contains a _____ -side polygon capsid (fill
in the blank) - ANSWER Bacteriophage; 20-sided
True or False: Structurally bacteriophages are similar to viruses that infect animals - AN-
SWER False. Bacteriophages have a distinct composition and structure
True or False. Structurally, bacteriophages are distinct from viruses that infect plant or ani-
mal cells. - ANSWER True. Bacteriophages are structurally distinct from viruses that infect
plant and animals cells.
Identify the following components of a bacteriophage (picture) - ANSWER 1. Capsid
2. Collar
3. Tail
4. Base
2
