Viruses (biology) – Flashcards
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Which structure has the least effect on the ability of a virus to infect and replicate in a host cell?
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ribosome
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Which best describes viruses?
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Viruses are nonliving infectious agents
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Which is included in a lysogenic cycle?
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a period of genetic integration
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Which virus has a structure that includes an outer lipid bilayer that is studded with proteins?
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influenza virus
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Which structure is labeled X in the diagram below?
http://media.education2020.com/evresources/3209-10-11/mc005-1.jpg
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capsid protein
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Which component of a virus is injected into an infected cell?
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nucleic acid
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Describe the lysogenic cycle
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It begins with the attachment of the virus to a host cell.
The DNA or RNA of the virus enters the cell and integrates with the DNA of the host cell, and a provirus is formed.
The provirus replicates with the host cell.
There are no symptoms until the virus enters the lytic cycle.
The virus enters the lytic cycle and symptoms appear
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describe the lytic cycle
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The virus attaches to a host cell.
The DNA of the host cell can be disassembled and the virus takes over metabolic activity.
The virus replicates using the cell's energy and materials.
The pieces of the virus made during replication are assembled.
Lysis and release of the virus occurs
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Describe how the structure of a virus aids in its ability to infect cells
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Capsid proteins interlock with a receptor site on the host cell.
The capsid protein and host cell receptor interlock like a puzzle piece.
Viruses vary in shape to attack the various types of receptors on cells.
The shapes of viruses include polyhedral, helical, enveloped, and complex.
Once the virus attaches to the host cell, it invades the cell and hijacks the DNA of the cel
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Contrast the structures of a virus and cell.
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Viruses are nonliving and infect host cells.
Cells are the smallest form of structure and function in living organisms.
Viruses cannot make their own food, do not contain a cell membrane, and cannot reproduce.
Cells contain a cell membrane, DNA, RNA, ribosomes, cytoplasm, and are able to grow and reproduce, and respond to stimuli.
Viruses contain one nucleic acid, a capsid, and an envelope.
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What usually happens to the host's DNA during the lytic cycle?
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It is destroyed
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In 2008, scientists in France discovered that a virus was capable of infecting another virus. Which theory might be supported by this information?
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A virus is living
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Consider the diagram that depicts the lysogenic and lytic cycles.
http://media.education2020.com/evresources/3209-10-11/mc022-1.jpg
In which step of the diagram are new viruses assembled?
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Step E