Intro History

Question 1

Introduction and History of the Field

Answer 1

-Microbiology is the study of microorganisms
-Prokaryotes (bacteria and Archaea)
-Some small Eukaryotes (Fungi, Yeast)
-Viruses

Question 2

Why is microbiology important

Answer 2

-Disease of humans, animals, and plants
-Human health: Are all microorganisms in our bodies bad for us?

Question 3

Facts about Microbes

Answer 3

-They contain the majority of the biomass on the planet (more than all plants and animal combined)
-There are about 10^30 microbial cells on earth (that is one trillion trillion microbes for each human)
-They can be found several kilometers up in the atmosphere and at least 10 km below the earth surface
-There are more microbial cells associated with your body than there are human cells

Question 4

What does Microbiology do that is important?

Answer 4

Model systems for basic studies of biological processes

Question 5

Origin of Earth

Answer 5

-cellular of Earth
-anoxygenic phototrophic bacteria
-Anoxic Earth
-Cyanobacteria
-transition to an oxygenated atmosphere
-modern eukaryotes
-algal diversity
-shelly invertebrates
-vascular plants
-mammals
-humans

Question 6

What were the leading causes of death in 1990 versus today?

Answer 6

-In 1990 infectious disease like influenza and pneumonia
-Today non microbial diseases like heart disease and cancer

Question 7

What are some milestone in the history of Microbiology?

Answer 7

-humans used microbes LONG before anyone ever recognized that they existed
-visual observations of microbes
-defeat of “spontaneous generation”
-infectious disease and acquired immunity

Question 8

Spontaneous Generation

Answer 8

-The idea that living organisms formed spontaneously from natural elements
-(Germs, maggots, and even mice would “magically” appear if you left food to rot)

Question 9

What did early experiments about spontaneous generation show?

Answer 9

-they showed that if the food was heated and them sealed from the air, then the rot didn’t occur.

Question 10

What are the competing theories to spontaneous generation?

Answer 10

-Air carries a “vital force” (spontaneous generation)
-Air carries “seeds or germ”

Question 11

Louis Pasteur (mid and late 1800s)

Answer 11

-Swan-neck flask
-vaccines for anthrax, fowl cholerae, and rabies

Question 12

Edward Jenner (late 1700s)

Answer 12

-vaccination for small pox from cow pox

Question 13

Joseph Lister (mid 1800s)

Answer 13

-Koch’s Postulates
-rules for clearly demonstrating the cause of an infectious disease

Question 14

1st Rule of Koch’s Postulates

Answer 14

The organism should be present in all animals suffering from the disease and should not be present in healthy individuals.

Question 15

2nd Rule of Koch’s Postulates

Answer 15

The organism should be grown in pure culture away from the animal body.

Question 16

3rd Rule of Koch’s Postulates

Answer 16

Cells from the pure culture, when inoculated into susceptible animals, should cause the disease symptoms.

Question 17

4th Rule of Koch’s Postulates

Answer 17

The organism should be re-isolated from these experimental animals and cultured again in the laboratory, after which it should still be the same as the original organism.

Question 18

Do all bacteria cause infections?

Answer 18

NO

Question 19

Enrichment techiques

Answer 19

-place an environmental sample under conditions that select for optimal growth of an organism with specific metabolic capabilities

Question 20

Martinus Beijerinck and Sergi Winogradsky (late 1800s/early 1900s)

Answer 20

-isolates from environmental soil and water samples
-demonstrated chemolithotroph
-demonstrated fixation of CO2 is not always associated with photosynthesis
-demonstrated the fixation of atmospheric nitrogen into cellular nitrogen
-sulfur bacteria by Winogradsky
-Nitrogen fixing Azotobacter by Beijerinck

Question 21

Chemolithotrophy

Answer 21

the use of inorganic compounds (sulfur, ammonia) to obtain energy