Chapter 1: History of Microbiology

Question 1

What did Robert Hooke (1665) do and discover? (2)

Answer 1

_ he used a crude microscope to view individual cells
- beginning of cell theory

Question 2

What is the cell theory?

Answer 2

all living organisms are composed of cells

Question 3

What did Antoni Van Leeuwenhoek do and discover? (3)

Answer 3

• amateur lens grinder
• built microscopes that could view living organisms
• called them animalcules

Question 4

What is Spontaneous generation?

Answer 4

• belief that some forms of life can arise from non-living matter

Question 5

What is biogenesis (1800s)?

Answer 5

living matter arises only from pre-existing living matter

Question 6

What did Louis Pasteur (1861) do and discover? (2)

Answer 6

• used swan necked flasks to disprove the theory of spontaneous generation
• developed the principle of aseptic technique

Question 7

What else did Louis Pasteur contribute to in the 1860s? (3)

Answer 7

• it was believed that air was responsible for turning sugars into alcohol
• He showed that microscopic yeast (fungi) convert sugar to alcohol through fermentation
• In the absence of oxygen, it is anaerobic

Question 8

Pasteur discovered fermentation. He also made a solution for souring. What is souring, and what was his solution? (3)

Answer 8

• souring occurs when bacteria turns alcohol into vinegar
• Heating beer or wine after fermentation would kill the bacteria and prevent spoilage
• this is known as pasteurization

Question 9

What is the germ theory disease?

Answer 9

• it was believed that disease was a punishment for crimes or misdeeds
• when the whole town got sick, it was the work of demons!

Question 10

How did Pasteurs work on fermentation disprove the germ theory disease? (2)

Answer 10

• Showed that microbes were responsible for chemical and physical changes to their environment
• this prompted the speculation that microbes could also be responsible for disease

Question 11

What did Joseph Lister (1860s) do and discover? (3)

Answer 11

• Used phenol to clean surgical instruments and treat surgical wounds
• This drastically reduced the incidence of surgical wound infections
• this led to the development of disinfectants and antiseptics

Question 12

What did John Snow (1850s) do and discover? (not in notes)

Answer 12

• people who got sick drank H2O from wells
• There could have been leakage with contaminants in the H2O source

Question 13

What did Robert Koch (1876) do? (6)

Answer 13

• Investigated the cause of anthrax
  1. isolated bacteria from the blood of infected cows
  2. Showed that a particular bacterium was present in all cases of the disease
  3. Then he injected the bacterium into healthy cows
  4. These cows contracted anthrax and died
  5. Re-isolated bacteria from the injected cows and showed that they were identical to his first sample

Question 14

What did Robert Koch’s work show? (2)

Answer 14

• Showed that a specific microbe was the cause of a particular disease
• Established a sequence of experimental steps that could be used to find the causative agent of other diseases - Koch’s postulates

Question 15

What bacteria is anthrax caused by?

Answer 15

bacilllus anthracis
- common in soil (that’s how the cows died)

Question 16

What did Edward Jenner observe?

Answer 16

• he observed that people who were previously sick with the mild disease cowpox did not get sick with smallpox

Question 17

What was Jenner’s experimental procedure? (3)

Answer 17

1. He purposely inoculated a young boy with cowpox
2. The boy became mildly ill
3. The boy recovered and became immune to smallpox

Question 18

How did Edward Jenner’s contribution affect the world?

Answer 18

• developed a vaccine to protect against the disease smallpox
• became important in the study of immunology

Question 19

What were Louis Pasteur’s contributions specifically in 1880? (3)

Answer 19

• bacterium that caused fowl cholera lost its ability to cause disease when grown in the lab for long periods of time
• still able to induce immunity to fowl cholera when injected into healthy birds
• Vaccination
  note: oxygen affects the genome of cholera

Question 20

What is the definition of vaccination?

Answer 20

• purposeful exposure to a killed or weakened microbe in order to induce an immune response

Question 21

What did Paul Ehrlich (1908) observe? (3)

Answer 21

• noticed that certain dyes stain bacteria differently than they stained animal cells
• So he proposed that a chemical might be found that would harm disease causing microbes without harming the host
• selective toxicity

Question 22

What is selective toxicity?

Answer 22

• the ability of a drug to target sites that are relative specific to the microorganism responsible for infection
• some times these sites are unique to the microorganism or simply more essential to survival of the microorganism, than to the host

Question 23

What antimicrobial did Paul Ehrlich eventually discover? (2)

Answer 23

• salvarsan, an arsenic derivative that could be used to treat syphilis
• beginning of chemotherapy

Question 24

What did Alexander Fleming do and discover? (2)

Answer 24

• noticed that mold inhibited bacterial growth on contaminated plates
• produced a natural compound called penicillin

Question 25

What is penicillin? (2)

Answer 25

• The first antibiotic
• An antimicrobial chemical produced naturally by bacteria or fungi

Question 26

Nomenclature: What did Carl Linnaeus discover (1674-1748)?

Answer 26

• naming system for microorganisms