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The Virus & The BacteriaThe Virus

� 20nm-60nm

� Not considered alive.

� Can only reproduce

inside the Host Cell.

� Specific – Attach only

to specific cells based

on the proteins in the

cell membrane.

The Virus Structure

� Made up of

� Nucleic Acids –

containing either, DNA

or RNA.

� Capsid- a protein coat

that surrounds the

Genetic material.

Virus ReproductionThe Lysogenic Cycle

Virus ReproductionThe Lytic Cycle

Virus Reproduction

� The Lysogenic Cycle

� Do not destroy the host

cell at first.

� Continue to reproduce

with the virus Genetic

Material inside.

�The Lytic Cycle

�Virulent virus

�Direct Death of the Host cell

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Hemorrhagic Fever

Ebola Marburg

Hemorrhagic FeverEbola

� Found in Primates

� Animal-Borne Virus

� RNA virus

� Incubation – 2-21 days

� Fever, headache, joint & muscle pain – rash

red eyes – Bleeding from all orifices.

Ebola

� Transmission – 1st patient

comes in contact with the

infected animal.

� Direct contact with blood

and/or secretions.

� Ebola Reston – airborne only

in monkeys

� Hot zones – Congo, Gabon,

Sudan

SARSSevere Acute Respiratory Syndrome

Hot Zone- China, Toronto

Symptoms – Flu like- fever,

headache, dry cough

Transmission- Person to

person contact, respiratory

secretion

Military action has been

taken to keep virus

controlled.

Small Pox

� Spans 1,000’s of years.

� 30% fatality rate

� 100% fatality rate in

the flat & hemorrhagic

strains.

� Eradicated from the

world

� Last U.S. case 1949

� World case -1977

Small Pox

� Humans are the natural host.

� Spread by face to face contact. – Also body fluids.

� Most Contagious during Early Rash continues till the last scab falls off.

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Small Pox

� Feared to be used as a

Biological Weapon

� Known vials Siberia,

Atlanta

� Believe – India,

Pakistan, China, Israel,

Iraq, North Korea, Iran,

Cuba, Taiwan, Former

Yugoslavia, France, Al-

Qaeda, Aum Shinrikyo

Small Pox

� Historical Facts

� The first urban Virus - arose 7,000 years ago in

large cities. Why?

� Pharaoh Ramses V – died of the pox

� Chinese worshiped the goddess of small pox

named T’ou Shen Niang-Niang

� India – the goddess what Shitala Ma

HIVHuman Immune Deficiency Virus

� Fastest Spreading

disease in Africa

� Effects white blood

cells. T-Cells

� T-cell count below 200

you have AIDS.

� Blood Tranmission

West Nile Virus

� Host – Birds

� Spread through mosquitoes

� Fever, headache, and body

aches, occasionally with skin

rash and swollen lymph nodes.

� Rare encephalitis

� 1% of mosquitos carry the

virus, 1% of those infected

will die.

The Bacteria

� Prokaryotic Cells

� Two Kingdoms

� Archaebacteria - The

extremists. 3 types

� Lives in Oxygen free environments

� High salt content

� Hot acidic waters

� Eubacteria

Bacteria-Eubacteria

� Many varieties

� Heterotrophic

� Saprobes – feed off the dead.

� Photosynthetic

� Chemosynthetic autotrophs - feed

off the break down of inorganic

substances. Reproduce Sexually

� Reproduce asexually – fission

� Reproduce sexually

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Reproduction – Genetic Recombination

� 1. Transformation – When a bacteria

transfers a piece of its DNA into another

bacteria creating a slightly different genotype

and phenotype.

� 2. Conjugation – when two bacteria form

pili between one another transfer genetic

material.

Bacteria - Structure

� Different Shapes

� Sphere - coccus

� Rods - bacillus

� Spirals – sprillium

� Structures

� Capsule

� Cell wall

� Plasma membrane

� Pili

� DNA

� Flagella

Antibiotics only Kill

Bacteria

Anthrax

� Direct contact

� Many different strains

� Found in lower vertebrates –

goats, sheep, cattle

� Three types

� Cutaneous – skin – death rare if

treated

� Inhalation – Cold-like – fatal

� Gastrointestinal – 25-60%

Flesh Eating Necrotizing Fasciitis

• Group “A” Streptococcus

with a mutation.

• Reproduces rapidly

• Tissue must be removed.

• Patient must be put into a

pressure chamber to

reduce the spread.

Bubonic Plague or Black Death

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Bubonic Plague or Black Death

� Swollen lymph nodes

(buboes, hence the

name), high fever, and

delirium.

� 90% Death Rate

� Killed 137 million

people

Lyme Disease

• Host is the Deer tick.

Botulism & E. Coli

• Botulism

• Muscle-paralyzing disease.

• Food-borne

• Anaerobic

• E. Coli

• 1,000 of strains

• Undercooked meat

• Sewage water

• Lives in intestines.

Bacteria can be

Good

Nitrogen Fixation

Nitrogen gas is changed

into a usable form to

make proteins, DNA,

RNA, & ATP

Found in the roots of

Legume plants .

Food Source

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Decomposer