VIRUSES
STRUCTURE
REPLICATION
Lysogenic Cycle
Lytic Cycle
temperate phage only
genome integrates into bacterial chromosome as prophage, with which it has two options:
can be replicated and passed onto daughter cells
can be directed to leave chromosome and start lytic cycle
destroy host cell DNA
production of new phages
virulent or temperate phage
lysis of host cell causing release of new phages
VIRUS an infectious agent that replicates genetic material into a host cell
Transmission
Host Range
each particular virus can infect cells of only a certain number of host cells
have the ability to crystallize, because they are not cells
largest barely visible under microscope
consists of nucleic acid enclosed in protein coat and some even surrounded by a membranous envelope
depending on type of virus (or rather genome); can be double stranded or single stranded DNA or double stranded or single stranded RNA.
capsid protein shell enclosing the viral genome, built from large # protein subunits called capsomeres
Capsid Shapes
bacteriophage or phages, virus that infects bacteria
polyhedral
rod-shaped
horizontal transmission - a plant is infected from an external source of the virus
vertical transmission - a plant inherits a viral infection from a parent
Vaccine
a harmless variant/derivative of pathogen that stimulates the host's immune system; to prevent community damage.
Pandemic - a global epidemic
Epidemic - a general outbreak of disease
Provirus - a viral genome that is permanently inserted into a host genome
Prion - an infectious agent that is a misfolded version of a normal cellular protein; appear to increase in number by converting correctly folded versions of the protein to more of them.
Retroviruses - an enzyme encoded by certain viruses that uses RNA as a template for DNA synthesis