Viruses Flashcards
Certain viruses affect different tissues and areas of the body
True
What is a virus?
Genetic structure that requires a living host to replicate.
What is a virus particle?
Extracellular form of a virus
Is the genome of viruses relatively large?
No, they contain only a few genes.
What is the Baltimore classification scheme?
Viruses that are classified by type of viral genome and its relationship to mRNA
How big are viruses typically?
20 to 300nm size range
Describe the structure of a virus.
Protein molecules in pattern surrounding nucleic acid.
Capsid surrounds the genome
What are capsomeres and nucleocapsids?
Subunit of capsid that is a building block.
Complex of nucleic acid and protein virion
What is a virion?
Structure of virus that exists outside a host cell
Two types of viral structure. What are they?
Naked and enveloped.
Difference is a lipid bilayer with embedded proteins.
Which type of viruses are the easiest to grow?
Bacteriophages
What are plaques?
Clear zones that develop on lawns.
What is the problem with plaque assays?
Some animal viruses do not show recognizable changes in cell cultures.
Name the steps involved in viral replication.
- ) Attachment
- ) Penetration
- ) Synthesis of material using cell machinery
- ) Assembly of viruses
- ) Release of mature virions
What is a permissive cell?
Cell that lets a virus go through full replication cycle
