9. Viruses Flashcards
1
Q
which are the 4 possible forms of the viral genome?
A
- double-stranded DNA
- single-stranded DNA
- double-stranded RNA
- single-stranded RNA
2
Q
molecules that build the capsid (the shell that encloses the viral genome)?
A
it is a protein shell built from protein subunits called CAPSOMERS and lipids too
3
Q
molecules that build the viral envelope?
A
- phospholipids and membrane proteins from the host cell
- proteins and glycoproteins of viral origin
4
Q
what class are RETROVIRUSES in?
A
class VI
5
Q
what enzyme do retroviruses contain?
A
Reverse transcriptase
6
Q
what genetic material do retroviruses contain?
A
they are enveloped viruses and contain double-stranded RNA
7
Q
which replication cycle do retroviruses undergo?
A
Lysogenic cycle
8
Q
steps of HIV infection
A
- HIV enters the host cell
- HIV’s reverse transcriptase molecules are released into the cytoplasm and catalyze the synthesis of viral DNA
- The viral DNA enters the cell’s nucleus and integrates into the DNA of the cell’s chromosomes. The integrated viral DNA is called PROVIRUS.
- The RNA-polymerase of the host cell transcribes the provirus into RNA molecules
9
Q
Provirus
A
the integrated viral DNA
10
Q
can the provirus leave the host’s genome?
A
never, it is permanent
11
Q
the functions of the transcribed RNA from viral DNA?
A
- as mRNA for the synthesis of viral proteins
- as genome for the new viruses that will assemble and leave the cell
12
Q
HIV’s genetic material
A
single-stranded RNA
