Virus Structure and Classification Flashcards
1
Q
What is a virus?
A
2
Q
What is a virion?
A
a complete virus particle is called a virion (virion size varies from 20–300 nm)
3
Q
Types of Viruses
A
4
Q
Prions
A
Prions are protein molecules without genes, which become infectious due to conformational changes in the prion protein. They are responsible for some neurologic disorders such as Kuru, CJD, mad-cow disease (discussed in persistent viral infection of the CNS).
5
Q
Viroids
A
Viriods are infectious circular RNA molecules without a protein shell. They are responsible for plant disorders (this information is for educational purpose).
6
Q
5 Types of Viral Infection
A
7
Q
A
8
Q
Virus Genome
A
DNA or RNA
9
Q
RNA Viruses
A
10
Q
DNA Viruses
A
11
Q
Capsid
A
- protein shell
- naked capsid
- nucleocapsid
12
Q
Envelope
A
- mainly derived from cellular membranes
- lipid bilayer
13
Q
A
14
Q
Naked Capsid Viruses
A
15
Q
Enveloped Viruses
A
- Derived from host cell plasma or nuclear membranes
- Lipid bilayer membrane containing virus specific proteins and/or glycoproteins called spikes or peplomers
- Envelope proteins bind to receptors on the host cell
- Help in fusion with the cell membrane
- Elicit immune responses, both humoral and cell mediated
16
Q
Protein (Capsid) Architecture
A
17
Q
Classification of Viruses
A
