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What is a “Pathogen
What is a “
Pathogen”?
”?
Definition: a disease causing agent.
V: Introduction to Viruses
What is a “Virus
What is a “
Virus”?
”?
Definition: a pathogen, or disease causing agent, not considered living because it cannot reproduce on its own. Virus Reproduction
A virus must have a HOST CELL to reproduce.
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Structure of a “
Structure of a “Virus
Virus””
Capsid: outer protein coat.
Genetic Material: DNA or RNA. V: Invasion of the Virus
“Lytic Cycle
Lytic Cycle””
“Lytic Cycle
Lytic Cycle””
Definition: process in which a virus enters a cell, makes a copy of itself, and causes the cell to burst.
(Viral Reproduction)
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“Stage A (1)
Stage A (1)””
“Stage B (2)
Stage B (2)””
The virus lands on the host cell and then injects its genetic material into the host cell.
The virus using the host cell to synthesize, or make, viral proteins (capsids) and nucleic acids (genetic material‐DNA or RNA).
“Stage C (3)
Stage C (3)””
“Stage D (4)
Stage D (4)””
The virus assembles (puts together) capsids and nucleic acids to prepare for release.
The host cell breaks open (lysing) and the newly assembled viruses begin to be released.
“Lysogenic Cycle
Lysogenic Cycle””
Definition: process by which a virus embeds its DNA into the DNA of the host cell and is replicated along with the host cell's DNA.
Lysogenic cycle is a viral reproduction cycle in which the virus is dormant until it enters the lytic cycle.
V: : Bacteriophage Bacteriophage Lytic Cycle
Lytic Cycle
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“Lysogenic Cycle
Lysogenic Cycle””
What is a “Retrovirus
What is a “
Retrovirus”?
”?
Definition: a virus that contains RNA as its genetic material instead of DNA.
Viruses cause “
Viruses cause “Disease
Disease””
How: by disrupting the body’s normal equilibrium. In many viral infections, viruses attach and destroy certain cells in the body, causing the symptoms of the disease.
“Influenza
Influenza””
(Flu or Grippe)
Definition: a highly infectious respiratory disease. Your best defense against this virus is to receive an annual vaccination (according to the Mayo Clinic).
“HIV”
HIV”
(Human Immunodeficiency Virus)
Definition: retrovirus that destroys white blood cells called helper T cells and causes the disease known as AIDS (Acquired I
Immune Deficiency Syndrome).
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What is a “Vaccine
What is a “
Vaccine”?
”?
Definition: a preparation of weakened or killed pathogens. When injected into the body, a vaccine sometimes prompts the body to produce immunity to the disease.
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What is “Immunity
What is “
Immunity”?
”?
Definition: the body's ability to destroy new pathogens.
V: : How Vaccines Work
How Vaccines Work
What are “
What are “Antibiotics
Antibiotics”?
”?
Definition: compounds that block the growth and reproduction of bacteria. DO NOT work on viral infections! Who is a “Immunologist
Who is a “
Immunologist”?
”?
Definition: a person who specializes in the immune system, to study the mechanism used by the virus t i f t ll
to infect cells.
If a company wants to develop antiviral drugs, they would need to ask a research immunologist.
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