Transcript Microbes

Microbes
The Scope of Microbiology
• Microbiology: The study of living things
too small to be seen without magnification
– Microorganisms or microbes- microscopic
organisms
– Commonly called “germs, viruses, agents…”
but not all cause disease and many more are
useful or essential for human life
Relative Microbial Sizes
• If poliovirus (27 nm) was the size of a quarter…
• Staphylococcus aureus (0.8 µm)
• Escherichia coli (0.7 x 2.5 µm)
• Saccharomyces cerevisiae (5 µm)
• Paramecium caudatum (50 x 250 µm)
• Amoeba proteus (800 µm)
Beach ball
Adult human
Elephant
Large yard
(2.5 acres)
10 city blocks
(100 acres)
Major Groups of
Microorganisms
• Bacteria, algae, protozoa, helminthes,
and fungi
• Viruses- noncellular, parasitic, proteincoated genetic elements that can infect
all living things, including other
microorganisms
There are six main types of microorganisms: 1.) bacterium, 2.) Fungus,
3.) Algae, 4.) Virus, 5.) Protozoan, 6.) Helminth.
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The six types of microorganisms
The Impact of Microbes on Earth: Small
Organisms with a Giant Effect
• Microorganisms have a profound
influence on all aspects of the earth and
its residents
Evolutionary Time Line
Importance of Microbes
1. Microbes are the earliest organisms
found in the fossil record
2. They perform essential reactions in the
environment
3.Microbes can be harnessed to work for
us
4.They sometimes cause infectious
diseases
The important contributions of microbes
in the earth’s ecosystems include the
following:
• a) photosynthesis by microalgae and
cyanobacteria produces molecular
oxygen and consumes carbon dioxide;
• b) decomposition and recycling of
organic matter by fungi and bacteria;
• c) cycling of inorganic compounds
such as nitrogen fixation by bacteria;
• d) and microbes such as microalgae,
protozoa, and fungi that serve as food
sources for other organisms, both
aquatic and terrestrial.
• Five different ways in which humans
exploit microbes for our benefit are:
• 1) for the production of foods such as
bread, cheese, beer, and yogurt by the
fermentation process.
• 2) for the production of enzymes and
drugs (e.g. insulin) with use of
recombinant DNA technology.
• 3) for use in the laboratory as model
organisms (e.g. yeasts) to study
genetics, molecular biology, and
cellular processes.
• 4) and for the production of vaccines
and use in gene therapy to improve
human health.
• 5) for bioremediation to clean up
pollutants and wastes.
Bioremediation
• Bioremediation- introducing microbes in
to the environment to restore stability or
clean up toxic pollutants
– Oil spills
– Chemical spills
– Water and sewage treatment
Value of Biodiversity
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Value of Biodiversity
• Ethical and aesthetic values are based on
our conscience
– Every species has a value of its own
– Humans should act as guardians or stewards
for the diversity of life around us
– How do we place a value on beauty ?
• What if it no longer existed ?
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