Download microbe detectives through the ages…

What is a Microorganism?
•
•
•
It is a living organism that is visible (as an individual
organism) only with the aid of a microscope. When
grouped together in chains or clusters, microorganisms
can be seen without a microscope.
Most are single-celled.
As with all living organisms, microorganisms have 6
basic needs:
Food
Water
Air
Temperature of environment
Reproduction
Waste
Infectious Disease
• An infectious disease is any disease
caused by a pathogen (germ) such as a
virus, bacteria, parasite, or fungus.
Pathogens
• “Pathogen” is the scientific name for germ.
Infectious diseases are caused by
pathogens. When your mom tells you to
wash your hands she wants you to get all
the pathogens off your hands so they
won’t bet in your mouth and body.
Examples
• Viruses- influenza, common cold,
measles, and hepatitis.
• Bacteria- Tuberculosis, cholera, typhoid
fever, and tetanus.
• Parasites- Parasites are organisms that
live off their hosts. Malaria, sleeping
sickness, and scabies.
• Fungus- fungal meningitis, ringworm, and
thrush.
MICROBE DETECTIVES
THROUGH THE AGES…
HOW FAR HAVE WE COME?
Here are some beliefs of the
past…
WHERE DO FROGS COME
FROM?
• OBSERVATION: Every year in the spring,
the Nile River flooded areas of Egypt
along the river, leaving behind nutrient-rich
mud that enabled the people to grow that
year’s crop of food. However, along with
the muddy soil, large numbers of frogs
appeared that weren’t around in drier
times.
• CONCLUSION: It was perfectly obvious
to people back then that muddy soil gave
rise to the frogs.
WHERE DO MICE COME FROM?
• OBSERVATION: In many parts
of Europe, medieval farmers
stored grain in barns with
thatched roofs (like
Shakespeare’s house). As a
roof aged, it was not
uncommon for it to start
leaking. This could lead to
spoiled or moldy grain, and of
course there were lots of mice
around.
• CONCLUSION: It was obvious
to them that the mice came
from the moldy grain.
WHERE DO FLIES COME FROM?
• OBSERVATION: Since there
were no refrigerators, the
mandatory, daily trip to the
butcher shop, especially in
summer, meant battling the
flies around the carcasses.
Typically, carcasses were
“hung by their heels,” and
customers selected which
chunk the butcher would carve
off for them.
• CONCLUSION: Obviously, the
rotting meat that had been
hanging in the sun all day was
the source of the flies.
For centuries, people based their
beliefs on their interpretations of
what they saw going on in the
world around them without testing
their ideas to determine the
validity of these theories.
Fortunately for us, we have come a
long way in scientific discoveries.
Some important people are…
ANTONY VAN
LEEUWENHOEK
• The first person to peer into a microscope was a
Dutch cloth merchant named Antony Van
Leeuwenhoek (lay-ven-hook). A self-taught
scientist, Leeuwenhoek discovered a way to
make magnifying lenses more powerful than any
previously made. Around 1668, he used a lens
no bigger than the head of a hat pin to create
the earliest know single-lens microscope. He
looked at scrapings from his teeth, and saw
some tiny organisms in the sample.
1860 LOUIS PASTEUR
• Louis Pasteur proves
the “germ theory of
disease,” stating that
every infectious
disease is caused by
a specific microbe.
1867 JOSEPH LISTER
• Joseph Lister
develops antiseptic
methods of surgerysuch as boiling
instruments – to curb
the infection of
wounds.
1928 ALEXANDER FLEMING
• Alexander Fleming
discovers that a mold
called Penicillium kills
bacteria, paving the
way for the use of
antibiotics.
Wanted Poster
Wanted Poster Topics
•
•
Protist Diseases
Malaria
African Sleeping Sickness
Giardiasis
Amoebic Dysentery
Toxoplasmosis
Bacterial Diseases
•
Anthrax
Bacterial Pneumonia
Black Plague
Botulism
Whooping Cough
Cat Scratch Disease
Flesh Eating Bacteria (strep throat)
Lyme Disease
Gangrene (Gas Gangrene)
Tetanus
Diphtheria
Traveler’s Diarrhea
Bacterial Meningitis
Tuberculosis
Rocky Mounted Spotted Fever
Salmonellosis
Typhoid Fever
•
•
Viral Diseases
•
Chickenpox
Polio
Mumps
Measles
Smallpox
Influenza (flu)
Ebola
Mononucleosis (Mono)
Plantar Wart
•
Fungal Diseases
•
Ringworm
Thrush