History and Discovery of Microorganisms Flashcards
Chapter 1
What is Microbiology?
The study of microorganisms—living organisms too small to see without a microscope.
What are Microorganisms?
Microscopic organisms such as bacteria, viruses, fungi, algae, and protozoa.
Microorganisms: Positive or Negative?
While some cause diseases, most are essential for maintaining environmental and biological balance.
Who invented the first microscope?
Robert Hooke in 1665, magnifying objects 30x.
What did Hooke observe?
Cork cells, fly eyes, and molds; first to describe microorganisms in Micrographia (1665).
Who was the first person to observe and accurately describe microorganisms (bacteria and protozoa) called animalcules
Also known as the father of microbiology
Antoine van Leeuwenhoek
Who developed Binomial Nomenclature?
Carolus Linnaeus in 1735, classifying organisms by genus and species.
Who first proposed contagion?
Girolamo Fracastoro (1546), identifying three modes: contact, objects, and air.
Who introduced handwashing in medicine?
Ignaz Semmelweis (1847) used chlorine water to prevent disease spread.
What caused cholera in 1854?
John Snow identified contaminated London water supplies as the source.
The Germ Theory of Diseases
States that microorganisms are the main cause of diseases
-Microorganisms are the causative agents of disease
-Microbes can spread through different modes of contact
-Once inside the body microbes reproduce and multiply casing damage and producing sisease symptons
This led to the devlopment of hygiene, sterilization, and vaccination help prevent diseases
Golden Age of Microbiology
(1854–1914)
Who disproved spontaneous generation?
Louis Pasteur’s Swan-Neck Flask experiment (1857).
Who discovered the smallpox vaccine?
Edward Jenner in 1798.
Who discovered bacterial endospores?
Ferdinand Cohn identified highly resistant bacterial structures.
19th century
What was Pasteur’s vaccine breakthrough?
Attenuating bacteria for cholera, anthrax, and rabies vaccines (1880s).
What is an Antitoxin?
Emil von Behring developed diphtheria treatment using antibodies (Nobel Prize, 1901).
What is the Petri Dish?
Invented by Julius Petri in 1887 for growing bacterial cultures on solid agar.
What is a Pure Culture?
A culture in which single type of microorganism isolated and grown, developed by Koch.
What are Koch’s Postulates?
Four criteria to establish a causal relationship between a microbe and a disease, developed by Robert Koch in the 1880s.
Postulate 1
The microorganism must be abundant in diseased organisms but absent in healthy ones.
Postulate 2
The microorganism must be isolated from a diseased organism and grown in pure culture.
Postulate 3
The cultured microorganism should cause disease when introduced to a healthy organism.
Postulate 4
The organism must be recovered from the infected animal and shown to be the same organism that was introduced
