viruses a tiny, non-living parasite (particle) that enters and reproduces inside a living host cell....

12
VIRUSES A tiny, non-living parasite (particle) that enters and reproduces inside a living host cell. Two types: 1. Active 2. Hidden

Upload: robyn-imogene-roberts

Post on 04-Jan-2016

230 views

Category:

Documents


0 download

TRANSCRIPT

Page 1: VIRUSES A tiny, non-living parasite (particle) that enters and reproduces inside a living host cell. Two types: 1. Active 2. Hidden

VIRUSES

A tiny, non-living parasite (particle) that enters and reproduces inside a living host cell.

Two types: 1. Active2. Hidden

Page 2: VIRUSES A tiny, non-living parasite (particle) that enters and reproduces inside a living host cell. Two types: 1. Active 2. Hidden

Characteristics of Viruses

Non-living Parasite Not a cell Cannot make or take in their own food Does not produce waste Multiply only in living cells

Page 3: VIRUSES A tiny, non-living parasite (particle) that enters and reproduces inside a living host cell. Two types: 1. Active 2. Hidden

Shapes of Viruses

Round (chicken pox, west nile) Tube/rod shaped (tobacco mosaic) Bullet (rabies) Robotlike (bacteriophage) Brick or thread like (Ebola)

Page 4: VIRUSES A tiny, non-living parasite (particle) that enters and reproduces inside a living host cell. Two types: 1. Active 2. Hidden

Virus Size

Smaller than cellsMeasured in nanometers (nm)

Question: Which is larger Bacterium or Influenza Virus?

Page 5: VIRUSES A tiny, non-living parasite (particle) that enters and reproduces inside a living host cell. Two types: 1. Active 2. Hidden

Naming Viruses

For the diseases they cause For the organism they infect After the person who discovered them

Page 6: VIRUSES A tiny, non-living parasite (particle) that enters and reproduces inside a living host cell. Two types: 1. Active 2. Hidden

Virus Structure

Two basic parts Protein coating – protects the virus Inner core – genetic material

Some may also contain a membrane envelope.

Page 7: VIRUSES A tiny, non-living parasite (particle) that enters and reproduces inside a living host cell. Two types: 1. Active 2. Hidden

ACTIVITY:

DRAW AND LABEL THE PARTS OF A VIRUS.ADD COLOR

Page 8: VIRUSES A tiny, non-living parasite (particle) that enters and reproduces inside a living host cell. Two types: 1. Active 2. Hidden

How Active Viruses Multiply

1. Attaches to host cell

2. Virus genetic information enters host cell

3. Viruses takes over host cell functions (becomes a bacterium)

4. Virus proteins and genetic information reproduces

5. Host cell burst open releasing new virus

Active viruses are always working and multiplying Examples: cold, flu

Page 9: VIRUSES A tiny, non-living parasite (particle) that enters and reproduces inside a living host cell. Two types: 1. Active 2. Hidden

How Hidden Viruses Multiply

1. Attaches to host cell2. Injects Virus genetic material3. Virus genetics becomes the host’s cells genetics4. Virus genetic material becomes active5. Takes over cell functions6. Host cell burst releasing virus

Stays inactive for several years (hide & attack) When host cell divides so to does the virus

genetics Example: Cold Sore

Page 10: VIRUSES A tiny, non-living parasite (particle) that enters and reproduces inside a living host cell. Two types: 1. Active 2. Hidden

Viruses in Our Living World

Viruses & Disease People:

Cold – short lived – active AIDS - Hidden

Plants: Animals:

Rabies Distemper

Usefulness of Viruses Gene Therapy – used to treat Cystic Fibrosis

Page 11: VIRUSES A tiny, non-living parasite (particle) that enters and reproduces inside a living host cell. Two types: 1. Active 2. Hidden

Examples of Common Viruses

Polio Chicken pox Smallpox Yellow fever Viral Meningitis West Nile Ebola

PolioPolio

Chicken poxChicken pox

Chicken pox

Small PoxSmall Pox

Yellow Fever

Viral MeningitisViral MeningitisWest NileWest Nile

Ebola

Yellow Fever

Page 12: VIRUSES A tiny, non-living parasite (particle) that enters and reproduces inside a living host cell. Two types: 1. Active 2. Hidden

Summarize

What is a Virus? Identifying basic structure and traits.