viruses pa state standards:. what are viruses? 1) a nucleic acid (dna or rna) surrounded by a coat...
DESCRIPTION
Nonliving Properties of Viruses 1) Not made of Cells (no organelles or cell functions). 2) Can’t grow or reproduce on their own (reproduce inside the cells of other organisms). 3) Can be crystallized & stored for years.TRANSCRIPT
VIRUSES
PA State Standards:
What are VIRUSES?
1) A nucleic acid (DNA or RNA) surrounded by a coat of protein.
2) Viruses are not considered to be alive (they are not in one of the five kingdoms).
Nonliving Properties of Viruses
1) Not made of Cells (no organelles or cell functions).
2) Can’t grow or reproduce on their own (reproduce inside the cells of other
organisms).
3) Can be crystallized & stored for years.
Examples of Viruses:Bacteriophage
Head
Tail
Capsid
DNA
Tail Fibers
Examples of Viruses:
Influenza VirusCapsid
RNA
Proteinspikes
What is a parasite
An organism that attaches itself and feeds off of another organism.
A parasite does harm to the organism it is attached to
Hookworm
What is a host
The organism that is harmed or hurt by the parasite
Example: You are the host to a mosquito
Bacteriophage Reproductive Cycle
1- Attach
Virus attaches to cell. Use tail to attach to cell membrane of cell.
Bacteriophage
Bacteria
2- Invade
Viral DNA invades cellVirus injects nucleicacid into the cell.
Viral DNA penetrates cell membrane/cell wall
Viral DNA slides into host cell
3- Copy
a) Virus’ nucleic acid attaches to DNA of the cell.
Viral DNA
Bacterial DNA
Bacteria is forced to make more & more viruses
3- Copy
b) DNA copies and makes new virusesVirus takes control of cell & makes new virus particles.
4- Release
Cell bursts releasing hundreds of new viruses
Bacteriophage Reproductive Cycle
5- VIRUSES & DISEASE
1) HUMANS
a) Colds
b) A.I.D.S.Aquired Immune Deficiency
SyndromeH.I.V. – Human Immunodeficiency Virus
5- VIRUSES & DISEASE
1) HUMANS
c) Polio
Iron Lung
F.D.R.Deformed Leg
Caused by Polio
5- VIRUSES & DISEASE
2) ANIMALS
Rabies
5- VIRUSES & DISEASE
3) PLANTS
Tobacco Mosaic Virus
How are viruses transmitted?
Direct contact Touching, body fluids, etc.
Vectors - mosquitoes, flies, etc
Airborne Spread by the air
Terms to know:
What happens when a disease spreads fast in a certain area?
An epidemic What system in your body is used to help stop
you from getting sick? The immune system What is a small amount of a virus injected into
your body to give you immunity called? A vaccine
CREDITS
http://www.cat.cc.md.us/courses/bio141/lecguide/unit2/viruses/lysosum.html