Viruses (Micro Packet 5) Flashcards
A mature virus particle
virion
A virion contains
one type of nucleic acid: DNA or RNA
Viruses are not
cells
a nucleic acid is surrounded by
a protein coat called a capsid
Why are viruses considered non living?
the are unable to reproduce outside of a living host
what are spikes used for and what do they cause
absorption and hemoglutination q
influenza infects
red blood cells
spikes are only found on
enveloped viruses
a naked piece of nucleic acid, like RNA that can be infectious is called a
viriod
Viruses multiply inside
living host cells using the host cells DNA, RNA, ribosomes to synthesize specialized infectious elements
Viruses are classified by
size, nucleic acid, morphology and the number of capsomeres
viruses get into the cell by
pinocytosis and phagocytosis
How do we study viruses in the laboratory
- we grow viruses in lab animals
- we grow viruses in embryonated eggs
- we grow & study biruses in cell culture the cells form a monolayer of cells
- we can grow them in bacterial cultures
how can we study viruses in bacterial cultures
the growth of viruses will produce a clear area on a lawn of bacterial growth called a plaque.
the ability of a virus is to infect an organism is regulated by a
- host species
- type of cells
- availability of the attachment site
- cell factors necessary for viral replication
Reproduction of viral multiplication
- adsorption
- penetration
- uncoating
- biosynthesis
- maturation
- release
Adsorption
a virus attaches to a cell membrane
penetration
the virus is englufed into the cell
uncoating
once inside the virus looses the capsid
biosynthesis
the viral DNA/RNA replicates helped by the host cell DNA. It organizes & manufactures protein capsids for the new progeny.
progeny
the new viral particles
maturation
new viruses appear in then ucleus or cytoplasm as inclusion bodies or elementary bodies
release
the new virus particles infect other cells, leaving the host cell gulted. upon leaving an envelope is acquired from pieces of the host cell membrane or nuclear membrane.
slow virus infections
is a disease process that occurs gradually over a long period of time
