Download A center core of DNA or RNA surrounded by a protein coat called a

9/27/2011
PORIFERA - SPONGES
The
simplest of
the animal
kingdom…
the only
phyla to
have
asymmetry.
VIRUSES
Are they living or non-living?
Contain genetic material (DNA or RNA)
Lack organelles
Cannot reproduce unless inside a host cell.
The word virus comes from the Greek word for
POISON
Cause many diseases.
VIRUSES
MORE ABOUT VIRUSES
VIRUS STRUCTURE:
Much
smaller than bacterial cells.
have only recently, last 60
years, learned anything about viruses.
Classified according to the types of cells
they attack.
Scientists
A
center core of DNA or RNA
surrounded by a protein coat
called a capsid.
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VIRAL REPRODUCTION:
LYTIC CYCLE
Injects its
nucleic acid
(DNA or RNA)
into the cell to
take over
cellular
activities.
LYTIC CYCLE
LYSOGENIC
CYCLE
Coexists with
the cell
without
destroying
the host cell.
LYSOGENIC CYCLE
RNA VIRUSES
Direct the production of proteins by the host cell.
RETROVIRUS = A special type of virus that can
make DNA ,which will produce new RNA, then in
turn, makes proteins that produce new viruses.
Example:
VIRAL DISEASES:
AIDS
Measles
Hepatitis
Chickenpox
Smallpox
Influenza
including H1N1
common cold (Rhinovirus)
West Nile
Polio
Herpes
The
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