Chapter 1: History of Microbiology Flashcards
What did Robert Hooke (1665) do and discover? (2)
_ he used a crude microscope to view individual cells
- beginning of cell theory
What is the cell theory?
all living organisms are composed of cells
What did Antoni Van Leeuwenhoek do and discover? (3)
- amateur lens grinder
- built microscopes that could view living organisms
- called them animalcules
What is Spontaneous generation?
- belief that some forms of life can arise from non-living matter
What is biogenesis (1800s)?
living matter arises only from pre-existing living matter
What did Louis Pasteur (1861) do and discover? (2)
- used swan necked flasks to disprove the theory of spontaneous generation
- developed the principle of aseptic technique
What else did Louis Pasteur contribute to in the 1860s? (3)
- 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
Pasteur discovered fermentation. He also made a solution for souring. What is souring, and what was his solution? (3)
- 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
What is the germ theory disease?
- it was believed that disease was a punishment for crimes or misdeeds
- when the whole town got sick, it was the work of demons!
How did Pasteurs work on fermentation disprove the germ theory disease? (2)
- 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
What did Joseph Lister (1860s) do and discover? (3)
- 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
What did John Snow (1850s) do and discover? (not in notes)
- people who got sick drank H2O from wells
- There could have been leakage with contaminants in the H2O source
What did Robert Koch (1876) do? (6)
- 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
What did Robert Koch’s work show? (2)
- 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
What bacteria is anthrax caused by?
bacilllus anthracis
- common in soil (that’s how the cows died)
What did Edward Jenner observe?
- he observed that people who were previously sick with the mild disease cowpox did not get sick with smallpox
What was Jenner’s experimental procedure? (3)
- He purposely inoculated a young boy with cowpox
- The boy became mildly ill
- The boy recovered and became immune to smallpox
How did Edward Jenner’s contribution affect the world?
- developed a vaccine to protect against the disease smallpox
- became important in the study of immunology
What were Louis Pasteur’s contributions specifically in 1880? (3)
- 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
What is the definition of vaccination?
- purposeful exposure to a killed or weakened microbe in order to induce an immune response
What did Paul Ehrlich (1908) observe? (3)
- 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
What is selective toxicity?
- 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
What antimicrobial did Paul Ehrlich eventually discover? (2)
- salvarsan, an arsenic derivative that could be used to treat syphilis
- beginning of chemotherapy
What did Alexander Fleming do and discover? (2)
- noticed that mold inhibited bacterial growth on contaminated plates
- produced a natural compound called penicillin
What is penicillin? (2)
- The first antibiotic
- An antimicrobial chemical produced naturally by bacteria or fungi
Nomenclature: What did Carl Linnaeus discover (1674-1748)?
- naming system for microorganisms
