Ch 13 (Viruses, Viroids, and Prions) Flashcards
What are the characteristics of viruses?
Small, acellular, infectious, DNA or RNA
What do viruses depend on the host for?
Metabolic pathway & reproduction/replication
What happens if the virus is in the environment?
No growth or response
What is a virion?
Extracellular state. Has nucleocapsid, phospholipid envelope.
What is the nucleocapsid made of?
Protein (capsid) and nucleic acid
True or False. Viruses have both DNA and RNA.
False.
True or False. Viruses infect specific host cells and why? Example?
True, due to complimentary proteins. Ex: HIV and T cells
What are generalist viruses? Example?
Infect many cells. Ex: West Nile Virus
What is capsid made of
Capsomeres (protein subunit)
What is the viral envelope made of?
Phospholipid bilayer and proteins.
What are glycoproteins in the envelope used for?
Attach to host cell & host recognition
Which viruses are more fragile, enveloped or naked?
Enveloped due to phospholipid bilayer
What is an example of an enveloped virus? Non enveloped?
Envelope is flu and non enveloped is cold
True or false, a cold is more severe than the flu.
False. Enveloped viruses are more severe
What are the five steps of lytic replication.
Attachment, entry, synthesis, assembly, and release.
Explain the steps of lytic replication (Attachment)
viral protein bind w/ host cell receptor
Explain the steps of lytic replication (Entry)
Lysozyme break cell wall. Nucleic acids and enzymes enter.
Explain the steps of lytic replication (Synthesis)
Enzyme degrade host chromosome, hijack host cell enzymes. Viral particle synthesis.
Explain the steps of lytic replication (Assembly)
Viral particle assembly
Explain the steps of lytic replication (Release)
Viral particle release, host cell is lysed (die)