History and Discovery of Microorganisms

Question 1

What is Microbiology?

Answer 1

The study of microorganisms—living organisms too small to see without a microscope.

Question 2

What are Microorganisms?

Answer 2

Microscopic organisms such as bacteria, viruses, fungi, algae, and protozoa.

Question 3

Microorganisms: Positive or Negative?

Answer 3

While some cause diseases, most are essential for maintaining environmental and biological balance.

Question 4

Who invented the first microscope?

Answer 4

Robert Hooke in 1665, magnifying objects 30x.

Question 5

What did Hooke observe?

Answer 5

Cork cells, fly eyes, and molds; first to describe microorganisms in Micrographia (1665).

Question 6

Who was the first person to observe and accurately describe microorganisms (bacteria and protozoa) called animalcules
Also known as the father of microbiology

Answer 6

Antoine van Leeuwenhoek

Question 7

Who developed Binomial Nomenclature?

Answer 7

Carolus Linnaeus in 1735, classifying organisms by genus and species.

Question 8

Who first proposed contagion?

Answer 8

Girolamo Fracastoro (1546), identifying three modes: contact, objects, and air.

Question 9

Who introduced handwashing in medicine?

Answer 9

Ignaz Semmelweis (1847) used chlorine water to prevent disease spread.

Question 10

What caused cholera in 1854?

Answer 10

John Snow identified contaminated London water supplies as the source.

Question 11

The Germ Theory of Diseases

Answer 11

States that microorganisms are the main cause of diseases
-Microorganisms are the causative agents of disease
-Microbes can spread
-Microbes reproduce and multiply
The immune system can fight infections
-Hygiene, sterilization, and vaccination help prevent diseases

Question 12

Golden Age of Microbiology

Answer 12

(1854–1914)

Question 13

Who disproved spontaneous generation?

Answer 13

Louis Pasteur’s Swan-Neck Flask experiment (1857).

Question 14

Who discovered the smallpox vaccine?

Answer 14

Edward Jenner in 1798.

Question 15

Who discovered bacterial endospores?

Answer 15

Ferdinand Cohn identified highly resistant bacterial structures.

Question 16

What was Pasteur’s vaccine breakthrough?

Answer 16

Attenuating bacteria for cholera, anthrax, and rabies vaccines (1880s).

Question 17

What is an Antitoxin?

Answer 17

Emil von Behring developed diphtheria treatment using antibodies (Nobel Prize, 1901).

Question 18

What is the Petri Dish?

Answer 18

Invented by Julius Petri for growing bacterial cultures on solid agar.

Question 19

What is a Pure Culture?

Answer 19

A single type of microorganism isolated and grown, developed by Koch.

Question 20

What are Koch’s Postulates?

Answer 20

Four criteria to establish a causal relationship between a microbe and a disease, developed by Robert Koch in the 1880s.

Question 21

Postulate 1

Answer 21

The microorganism must be abundant in diseased organisms but absent in healthy ones.

Question 22

Postulate 2

Answer 22

The microorganism must be isolated from a diseased organism and grown in pure culture.

Question 23

Postulate 3

Answer 23

The cultured microorganism should cause disease when introduced to a healthy organism.

Question 24

Postulate 4

Answer 24

The organism must be recovered from the infected animal and shown to be the same organism that was introduced