Introduction to Microbiology
BIO 6
Denise Lim
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ParScore Scantrons for
Lecture Tests
z Orange, 8.5" X 11"
z Do not wait until the day of the exam to buy
them
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Use Your Textbook Wisely
z
z
z
z
Glossary and Index
Appendices
"Check Your Understanding"
Study Outlines
At end of chapters
z Review and Study Questions at end of
chapters
Answers in the back of the book
3
Some other words of advice
z Manage your time well
z Pay attention to detail
z Learn to be a good communicator
z Be professional
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What is Microbiology?
z The study of organisms usually
too small to see with the naked
eye
Requires a microscope
z Microorganisms include:
Bacteria, archaea, fungi, protozoa,
algae, viruses, and animal parasites
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How small
is small?
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Why do we care about
microbes?
z Some can make us sick (germs)
z Most are beneficial
Important part of food chain:
photosynthesis to decomposition (rot)
Found in our bodies (probiotics)
Fermentation: cheese, yogurt, wine,
beer, vinegar, bread
Pharmaceuticals and medicine
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Binomial nomenclature
(naming microorganisms)
z Two names: Genus and species
Always italicized or underlined
z Genus name:
Always capitalized
Usually a noun
z Species name:
Always lower case
Usually an adjective, sometimes a
proper noun
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All living organisms are either
prokaryotes or eukaryotes
Refers to arrangement of genetic
material (DNA) in cells
- karyote means “before” nucleus
 Eu - karyote means “true” nucleus
 Pro
Prokaryotes have DNA spread
throughout cytoplasm
Eukaryotes have DNA within a
membrane bounded nucleus
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Prokaryotes vs. Eukaryotes
Prokaryotes are either bacteria or
archaea
All are single-celled organisms
Most are much smaller (100 - 1000X
smaller) than eukaryotic cells
Eukaryotes are everything else:
Fungi, protistans, plants and animals
Can be either single- or multi-celled
organisms
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Bacterial cell on left is 1000X smaller
than eukaryotic cell on right
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Size Comparison of
two prokaryotes & a eukaryote
Prokaryotes
Epulopiscium:
700 µm
Escherichia
coli: 0.5 - 2 µm
Eukaryote
Paramecium:
50 µm
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Are viruses living?
Bacterial Virus (T4)
Animal Virus (Ebola)
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Why are viruses nonliving?
Noncellular
Composed of genetic material (either
DNA or RNA) surrounded by a protein
coat
No metabolic capabilities
Cannot reproduce independently
No ability to regulate or respond
to environment
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What features define life?
Complex organization composed of cells
Ability to grow and develop
Ability to convert energy for own use
Ability to reproduce genetically similar
offspring
Presence of genetic material: DNA & RNA
Ability to regulate internal environment
(homeostasis)
Ability to respond to environmental stimulus
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Important Historical Events:
1600's & 1700's
Development of the Microscope
Animicules visualized
Discovery of immunization &
vaccines
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1800's
Development of Cell Theory
Fermentation and Pasteurization
Germ Theory of Disease
Antisepsis and Disease
Importance of hand washing
Antiseptics: chemical compounds that
could kill germs
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Robert Koch
1843 - 1910
Developed pure culture
techniques
Proved that Bacillus
anthracis caused the
disease anthrax in cattle
Developed Koch’s
Postulates: rules for
proving a specific microbe
caused a specific disease
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Application of Koch’s
Postulates
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1900's
Discovery of penicillin and other
antimicrobial agents
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Staphylococcus aureus inhibition
by fungus Penicillium antibiotic
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1900's
DNA is the genetic molecule
Genetic Code - 1960’s
Central Dogma
Recombinant DNA technology 1970's & 1980's
Human Genome Project
Personal “-omics”
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