LECTURE 1 : DISCOVERY OF MICROORGANISMS

Question 1

In 1668, he demonstrated that maggots could not arise spontaneously from decaying meat.

The results of his investigation invalidated the long- held belief that life forms could arise from non-living things.

Answer 1

Francesco Redi (1626-1697)

Question 1

He mentioned that simple invertebrates could come from spontaneous generation.

Answer 1

Aristotle (384 – 322 BC)

Question 2

He improved the previous experiments of Needham by heating the broth that was transferred into a sealed jar.

He observed that no growth took place as long as the
flasks remained sealed.

He proposed that air transports microorganisms into
the culture medium.

He concluded that microorganisms from the air
probably had entered Needham’s concoction after they were boiled.

Answer 2

Lazzaro Spallanzani (1729-1799)

Question 3

He observed that the sealed flask with boiled mutton broth became cloudy after standing.

He asserted that organic matter possessed a “vital force” that could give rise to life.

Answer 3

John Needham (1731-1781)

Question 4

He challenged the concept of spontaneous generation with biogenesis.

Answer 4

Rudolf Virchow (1821-1902)

Question 5

He observed that no growth occurred in a flask that contained a nutrient solution after allowing the air to pass through a heated tube.

Answer 5

Theodor Schwann (1810-1882)

Question 6

They noticed that no growth took place after allowing the air to pass through a sterile cotton wool placed on a flask with heat-sterilized culture medium.

Answer 6

Heinrich Schröder (1810-1885) and Theodore von Dusch (1824-1890)

Question 7

He disproved the theory of spontaneous generation.

He proved that while the air does not generate microbes, microorganisms are indeed present and can
contaminate a sterile solution.

He provided evidences that microorganisms could not
originate from “mystical forces” present in non-living
materials.

He improved the wine-making processes by
introducing the concept of fermentation and “pasteurization”

Answer 7

Louis Pasteur (1822-1895)

Question 8

He showed that dust carry germs that could contaminate a sterile broth.

Answer 8

John Tyndall (1820-1893)

Question 9

He discovered that there are bacteria that could withstand a series of boiling because of heat resistant structures known as endospores.

Answer 9

Ferdinand Cohn (1828-1898)

Question 10

He showed the importance of oxygen to life.

Answer 10

Antoine-Laurent Lavoisier (1743-1794)

Question 11

He explained that yeast cells are responsible for the conversion of sugars to alcohol.

Answer 11

Theodor Schwann

Question 12

He described that certain microorganisms known as yeasts convert sugar to alcohol in the absence of air, a process known as fermentation.

Answer 12

Louis Pasteur

Question 13

He stated that the souring and spoilage of wine are caused by different bacteria. He also proved that in the presence of air, bacteria convert the alcohol in the beverage into vinegar or acetic acid.

Answer 13

Louis Pasteur

Question 14

To resolve the problem in the wine industry, he suggested the minimal heating of beers and wines that is sufficient to kill most of the bacteria also known as pasteurization.

Answer 14

Louis Pasteur

Question 15

He demonstrated that routine handwashing can prevent the spread of diseases.

Answer 15

Ignaz Semmelweis (1816-1865)

Question 16

He introduced the system of antiseptic surgery.

Answer 16

Joseph Lister (1827-1912)

Question 17

He was first to show irrefutable proof that bacteria indeed cause diseases.

Answer 17

Robert Koch (1843-1910)

Question 18

He discovered Bacillus anthracis, the causative agent of anthrax, in 1876.

Answer 18

Robert Koch (1843-1910)

Question 19

He discovered Mycobacterium tuberculosis, which is the causative agent of pulmonary tuberculosis in 1882.

Answer 19

Robert Koch (1843-1910)

Question 20

He was the first to cultivate bacteria on boiled potatoes,
gelatin, meat extracts, and protein.

Answer 20

Robert Koch (1843-1910)

Question 21

He developed a culture medium for observing bacterial
growth isolated from the human body.

Answer 21

Robert Koch (1843-1910)

Question 22

He pioneered in promoting among surgeons the handwashing before and after an operation, the wearing of gloves, sterilizing of surgical instruments, and the use of phenol as an antimicrobial agent for
surgical wound dressing.

Answer 22

Joseph Lister (1827-1912)

Question 23

It is a form of sterilization in the 19th century that uses moist heat for three consecutive days to eradicate vegetative cells and endospores.

Answer 23

Tyndallization

Question 24

He developed the vaccine against anthrax (1881) and
rabies (1885).

Answer 24

Louis Pasteur

Question 25

1. The microorganism must be present in every case of the disease but absent from a healthy host.
2. The suspected microorganism must be isolated from a diseased host and grown in a pure are culture.
3. The same disease must be present when the isolated microorganism is inoculated into a healthy host.
4. The same organism must be isolated again from the diseased host.

Answer 25

KOCH’S POSTULATES

Question 26

He introduced the use of culture media.

Answer 26

Walther Hesse (1846-1911)

Question 27

She suggested the use of agar, a solidifying agent, in the preparation of the culture media.

Answer 27

Fanny Hesse (1850-1934)

Question 28

He developed the Petri dish, which is a circular glass or plastic plate for holding the culture media.

Answer 28

Julius Richard Petri (1852-1921)

Question 29

They developed the enrichment-culture technique and the use of selective media.

Answer 29

Martinus Beijerinck (1851-1931) and Sergei Winogradsky (1856-1953)

Question 30

He introduced the concept of vaccination

He collected scrapings from cowpox blisters and inoculated a healthy volunteer by scratching it person’s
arm with a pox-contaminated needle.

Answer 30

Edward Jenner (1749-1823)

Question 31

Used the term “vaccine” for an attenuated culture.

Made a series of experiments to produce attenuated strains of bacteria.

They were able to prove that when attenuated strains are introduced into a healthy host, the latter remains protected against the virulent agent.

Answer 31

Louis Pasteur (1822-1895) and Pierre Paul Emile Roux (1853-1933)

Question 32

He created a porcelain bacterial filter and developed the anthrax vaccine together with Pasteur.

Answer 32

Charles Chamberland (1851-1908)

Question 33

He prepared antitoxins for diphtheria and tetanus.

Answer 33

Emil von Behring (1854-1917)

Question 34

He was the first to describe the cells of the immune system and the process of phagocytosis.

Answer 34

Élie Metchnikoff (1845-1916)

Question 35

He discovered the streptomycin and neomycin antibiotics.

He was regarded as the “Father of Antibiotics” by some historians because he discovered antimicrobials before the hype of penicillin.

Answer 35

Selman Waksman (1888-1973)

Question 36

He accidentally discovered the antibiotic penicillin (Penicillium notatum).

He discovered the lysozyme.

Answer 36

Alexander Fleming (1881-1955)

Question 37

They made the purification process for penicillin and the clinical trials to humans.

Answer 37

Howard Florey (1898-1968) and Ernst Chain (1906-1979)

Question 38

He was the first to propose the correct biochemical structure of penicillin.

Answer 38

Edward Abraham (1913-1999)

Question 39

He discovered salvarsan (arsphenamine) for the treatment of syphilis.

Answer 39

Paul Ehrlich (1854-1915)

Question 40

It is the use of chemical substances in the treatment of diseases.

It also refers to the chemical treatment of non- infectious diseases, such as cancer.

Answer 40

Chemotherapy