Post on 18-Dec-2015
Not the Virus!If it is not alive, We can’t kill it -- We can only wish to
contain it!
What the heebie geebies is this?
Major Components of ALL VirusesPROTEIN COAT CALLED A CAPSIDSOME TYPE OF NUCLEIC ACID
What is the main difference between bacterial viruses and animal viruses?
How the nucleic acid enters the host cell
INJECTION VS. ENGULFMENT
PROK ANIMAL
Tobacco Mosaic Virus
First virus discovered in tobacco plants. Does not harm humans.
AdenovirusCommon fluRespiratory system infectionNot serious
InfluenzaCommon fluCan affect birds and humansCan cause epidemics- Spanish Flu
BacteriophageVirus that infects a bacteriaDo not harm humans
Figure 19-10 Lytic and Lysogenic Infections
Viral reproduction: Lytic CycleHost range: infection of a limited range of host cells (receptor molecules on the surface of cells)The lytic cycle: 1- attachment2- injection3- hydrolyzation4- assembly5- releaseResults in death of host cellVirulent virus (phage reproduction only by the lytic cycle)
Viral reproduction: Lysogenic Cycle
Genome replicated w/o destroying the host cell
Genetic material of virus becomes incorporated into the host cell DNA (prophage DNA)
Temperate virus (phages capable of using the lytic and lysogenic cycles)May give rise to lytic cycle
DNA VIRUS CYCLE
HERPES!!!!!!!! Is it in you?!
After the initial infection, some experience sporadic episodes or outbreaks.
Caused by STI and fluid contact
Only transmitted during outbreak or with sores…hard to transfer during latency
Reverse transcriptase Use enzyme reverse transcriptase to
transcribe RNA into DNA
Retroviruses Contain reverse transcriptaseInserts DNA into host cellCan lay dormant for yearsHas been linked to cancer
RETROVIRUS CYCLE
Lysogenic Lytic
VaccinesBiological preparation that improves
immunityContains an agent that resembles a
virus/disease causing microorganismStimulates immune system to recognize and
destroy