VirusesChapter 2.1

No, not this kind! The kind that make you really physically sick.

What are Viruses?

1. non-living particle, no living characteristics

2. not a cell

3. invades and multiplies inside a living cell

4. does not use energy to grow or respond to surroundings

5. needs a “Host” a source of energy (you) for the virus to multiply

6. acts like a parasite, causing harm to the host

Naming Viruses

1. After a disease they caused1. Poliomyelitis

2. Organisms they infect1. Bacteriophage –

a virus infecting bacteria

3. A place they are found

4. Scientists who discover them

Polio-an infectious disease, causing motor problems, paralysis

Viruses Multiply

Active VirusesMakes copy after

copy of new virusesHost releases

viruses

Hidden VirusesSits in hostInactiveAll at once

becomes activeCold soreStress

Hides again

5. Viruses and Living World

Can cause• Disease• Death• Harm to plants

and animals

Can be helpful to• Scientists• Gene therapy• Medical

treatment

BACTERIA

Two types of cells

Eukaryotic CellContains a nucleusMore evolved cellprotists, fungi, animals, plants

Prokaryotic CellContains NO nucleusPrimitive (older) cellBACTERIA

Bacteria CellsDiscovered by Anton van

Leeuwenhoek in the 1600s

Unicellular organisms that contain CYTOPLASM -Holds everything RIBOSOMES-Produce Proteins

Come in three shapesSpherical Rod Spiral

Bacteria contains

FLAGELLUM: a tail that helps them to move

Two Kingdoms of Bacteria

1. Archeabacteria“Ancient” bacteriaSurvives in extreme temperaturesEarth’s earliest life forms.

2. EubacteriaDo not live in extreme

environmentsMillions live in your bodyAdds oxygen to Earth’s

atmosphere

Bacteria uses Respiration: breaking down food to release energy

Two Types of Bacterial Reproduction

Asexual Reproduction – Reproduction with only 1 parent with offspring identical to parent

Binary Fission – One bacteria cell divides to form two identical cells

Sexual Reproduction –

• 2 parents combine genetic material to form a new, different offspring

• Conjugation – One bacterium transfers genetic material to another bacterium through a thin bridge

Bacteria Survival Needs Food

• AUTOTROPHS•Makes their own

food•Uses sun’s energy•Chemical

substances

• HETEROTROPHS•Can’t make

its own food•Consumes

autotrophs•Consumes

other heterotrophs

algae

Food chain

Uses of Bacteria1. Fuel:

• methane gas

2. Food: • cucumbers to pickles• milk to buttermilk

3. Environmental Recycling• Decomposers break down dead organisms

into chemicals

4. Environmental Cleanup

5. Health & Medicine• Antibiotics

Ch. 2.3 Viruses, Bacteria, and Health

Ch. 2.3 Viruses, Bacteria, and Health

Infectious Diseases Illness passing from one organism to

another

Infectious Diseases Illness passing from one organism to

another

Four Ways to get ill

1. Contact with infected person

2. Contaminated object3. Infected animal4. Environmental source

Four Ways to get ill

1. Contact with infected person

2. Contaminated object3. Infected animal4. Environmental source

Contact with Infected PersonContact with Infected Person Touching Hugging Kissing

Can transfer cold sores

Sneezes Coughs Flu

Through drops of infected moisture in the air

Touching Hugging Kissing

Can transfer cold sores

Sneezes Coughs Flu

Through drops of infected moisture in the air

Contact with Contaminated ObjectContact with Contaminated Object Viruses survive outside of the body

Spread on objects Utensils Cups Toothbrushes Cell Phones iPods Computers

Contaminated food/water lip gloss, chapstick, sharing or trading

food

Viruses survive outside of the body

Spread on objects Utensils Cups Toothbrushes Cell Phones iPods Computers

Contaminated food/water lip gloss, chapstick, sharing or trading

food

Contact with an AnimalContact with an Animal Animal bites

Rabies West Nile

Virus Ticks Mosquitoes

Animal bites Rabies West Nile

Virus Ticks Mosquitoes

Mosquitoes

West Nile Virus

Mosquitoes

West Nile Virus

Contact with Environmental Sources

Contact with Environmental Sources

Salmonella BacteriaFood poisoningEggs, poultry, meat

BotulismFood poisoningBacteria making a toxin

Salmonella BacteriaFood poisoningEggs, poultry, meat

BotulismFood poisoningBacteria making a toxin

Common Infectious DiseasesCommon Infectious Diseases

VIRAL AIDS Chicken Pox Flu Measles Polio Rabies

VIRAL AIDS Chicken Pox Flu Measles Polio Rabies

BACTERIAL Food Poisioning Lyme Disease Strep Throat Tetanus

(lockjaw) Tuberculosis

BACTERIAL Food Poisioning Lyme Disease Strep Throat Tetanus

(lockjaw) Tuberculosis

Vaccines: substance stimulates production of chemicals to prevent the spread of infectious disease