Introduction to Microbiology Lecture Notes

Comprehensive vocabulary flashcards covering the history, major figures, and classification systems of microbiology based on lecture slides.

Hippocrates

The “father of Western medicine” who believed that diseases had natural, rather than supernatural, causes.

Thucydides

A historian who observed that survivors of the Athenian plague were subsequently immune to the infection.

Marcus Terentius Varro

Proposed that disease could be caused by “certain minute creatures . . . which cannot be seen by the eye.”

Robert Hooke

Built the first compound microscope ($1635–1703$), published Micrographia, and coined the term “cell.”

Antonie van Leeuwenhoek

A Dutch cloth draper ($1632–1723$) who built single-lens magnifiers and was the first to observe single-celled microbes in $1683$, calling them “small animals.”

Louis Pasteur

Discovered the microbial basis of fermentation in the $1860s$, developed vaccines for Fowl cholera and Rabies, and used “swan-neck” flasks to show that boiled contents remain free of microbial growth.

Germ theory of disease

The theory that many diseases are caused by microbes.

Robert Koch

German physician ($1843–1910$) and founder of the scientific method of microbiology who applied his methods to lethal diseases such as anthrax.

Angelina and Walther Hesse

Researchers who developed the use of agar as a solid medium for the growth of pure cultures.

Julius Petri

Inventor of the double-dish container used for culturing microorganisms.

Koch's Postulates

A set of four criteria defining the causative agent of a disease: microbe presence in all cases, isolation in pure culture, infection of healthy host, and re-isolation of the same strain.

Lady Mary Montagu

Introduced the practice of smallpox inoculation to Europe in $1717$.

Edward Jenner

Deliberately infected patients with matter from cowpox lesions to develop the practice of vaccination ($1749–1823$).

Immunization

The stimulation of an immune response by deliberate inoculation with an attenuated (weakened) pathogen.

Ignaz Semmelweis

Ordered doctors to wash their hands with chlorine, an antiseptic agent, in $1847$.

Joseph Lister

Developed carbolic acid in $1865$ to treat wounds and clean surgical instruments.

John Snow

Known for his work on the Cholera epidemic in London in $1854$.

Florence Nightingale

Founder of the science of medical statistics who devised the “polar area chart” during the Crimean War ($1853-6$).

Alexander Fleming

Discovered in $1929$ that Penicillium mold generated a substance that kills bacteria.

Howard Florey and Ernst Chain

Purified penicillin in $1941$ to create the first commercial antibiotic to save human lives.

Dmitri Ivanovsky

Studied tobacco mosaic disease in $1892$ and discovered that the agent of transmission could pass through a porcelain filter that blocked bacteria.

Martinus Beijerinck

Concluded that the agent of tobacco mosaic disease is not a bacterium because it passes through filters that retain bacteria.

Wendell Stanley

Purified and crystallized the filterable agent known as Tobacco mosaic virus (TMV).

Sergei Winogradsky

Discovered lithotrophs, developed enrichment cultures, and built the Winogradsky column to study microbes in natural habitats ($1856–1953$).

Lithotrophs

Organisms that feed on inorganic material.

Carolus Linnaeus

Swedish botanist ($1707–1778$) and famous classifier of species who found microbial diversity bewilderingly difficult to classify.

Ernst Haeckel

Rendered a tree of life in $1866$ with three kingdoms (Plantae, Protista, Animalia) and later added Monera for unicellular organisms lacking a nucleus.

Microbial Species Working Definition

A standard requiring $95\%$ similarity of DNA sequence.

Lynn Margulis

Proposed the endosymbiosis theory ($1938–2011$), suggesting eukaryotic organelles like mitochondria and chloroplasts evolved from engulfed prokaryotic cells.

Three Domains of Life

Bacteria, Archaea, and Eukarya, as established in the phylogenetic tree by Woese and Fox.

Proteobacteria

The respiring prokaryotic organisms identified as the ancestors of mitochondria in the endosymbiosis model.

Ernst Ruska

Developed the electron microscope, which revealed the internal structure of cells.

Theodor Svedberg

Developed the ultracentrifuge, enabling the separation of subcellular parts.

Bacterial Sizes

Typical viruses measure about $100\,nm$, bacteria measure about $1\,\mu m$, and plant/animal cells measure $10–100\,\mu m$.

Coccobacillus

A bacterial shape that is a combination of spherical (coccus) and rod-shaped (bacillus).

Giardia lamblia

An intestinal protozoan parasite that infects humans and other mammals, causing severe diarrhea.

Candida albicans

A unicellular fungus (yeast) that is the causative agent of vaginal yeast infections and oral thrush.

Endosymbiont

A living organism that lives inside a larger organism.