Chapter 1: The Main Themes of Microbiology

What is microbiology?

The study of organisms too small to be seen without magnification

What are the six types of microorganisms discussed?

Bacteria, viruses, fungi, protozoa, algae, and helminths

What does medical microbiology study?

The effect of microorganisms on human beings

What do public health microbiology and epidemiology do?

Monitor and control the spread of diseases in communities

What does the CDC do with disease information?

Collects disease statistics and publishes them in the MMWR

What is biotechnology?

Using the natural abilities of microbes to improve lives and health through products and technologies

What is genetic engineering?

Deliberately altering an organism’s genetic makeup to create novel organisms

What is industrial microbiology?

Scaling microbial processes up to produce large quantities of desired products

What does immunology study?

Protective substances and reactions caused by invading microbes and harmful entities

What does agricultural microbiology study?

Relationships between microbes and domesticated plants and animals

What do plant specialist study in agricultural microbiology?

Plant diseases, soil fertility, and nutritional interactions

What do food microbiologists study?

Microbes’ effects on food spoilage, food-borne disease, and food production

How long have bacteria-like organisms existed on Earth?

About 3.5 billion years

What is a prokaryote?

A simple cell that lacks a nucleus and membrane-bound organelles

What is a eukaryote?

A cell with a nucleus and membrane-bound organelles; may be uni- or multicellular

What is a virus?

An acellular parasitic particle composed of nucleic acid and protein

What is a major structural difference between prokaryotes and eukaryotes?

Prokaryotes lack nuclei; eukaryotes have nuclei and membrane-bound organelles

What is an example of bacterium discussed?

Mycobacterium tuberculosis, a rod-shaped bacterium

What is an example of a fungus discussed?

Histoplasma capsulatum, which causes Ohio Valley fever

What are algae?

Microorganisms, including forms such as desmids, Spirogyra, and diatoms

What is an example of a virus discussed?

Herpes simplex virus, which causes cold sores

What is an example of a protozoan discussed?

Oxytricha trifallax, which uses cilia for movement

What are helminths?

Worms; Trichinella spiralis is an example that causes trichinellosis

What is biotechnology used for?

Producing foods, drugs, and vaccines using living organisms

What is bioremediation?

Using living organisms to remedy an environmental problem

How can microorganisms help with radioactive waste?

Certain bacteria can reduce and detoxify radioactive waste

What is true of most microorganisms?

Most are free-living, relatively harmless, beneficial, and often essential to life

What is a parasite?

An organism that lives on or in a host and damages the host

What is a pathogen?

A microbe that causes harm or disease

About how many different microbes cause disease?

Nearly 2000 different microbes

According to the lecture, how many new infections occur worldwide each year?

About 10 billion new infections per year

According to the lecture, how many deaths occur from infections yearly?

About 13 million deaths per year

What are the major historical foundations of microbiology?

Microscopy, the scientific method, medical microbiology, and microbiology techniques

What was spontaneous generation?

The belief that life could arise from vital forces in nonliving or decomposing matter

What is the theory of biogenesis?

The idea that livings things can only arise form other living things

Who disproved spontaneous generation?

Louis Pasteur

What did Edward Jenner observe about cowpox?

Cows had a form of pox similar to smallpox

What was Jenner’s hypothesis?

Cowpox could provide protection against smallpox

What did Jenner’s first vaccination experiment involve?

He inoculated a boy with material from a cowpox blister

What happened when Jenner later exposed the boy to smallpox?

The boy did not acquire smallpox and appeared protected

How did Jenner demonstrate reproducibility?

He inoculated 23 additional subjects with cowpox, who remained protected

What disease is now eradicated through vaccination?

Smallpox

What did John Tyndall and Ferdinand Cohn demonstrate

Some microbes have heat-resistant forms

What did Ferdinand Cohn identify as heat-resistant bacterial forms?

Bacterial endospores

What did Ferdinand Cohn identify as heat-resistant bacterial forms?

Bacterial endospores

What does sterility require?

Elimination of all life forms, including endospores and viruses

What did Oliver Wendell Holmes observe about childbirth?

Home births had fewer infections than hospital births

What did Ignaz Semmelweis connect to infections?

Physicians going directly from autopsy rooms to maternity wards

What did Joseph Lister introduce?

Aseptic techniques to reduce microbes and prevent wound infections

What is an example of an aseptic technique?

Proper hand washing and chemical disinfection before surgery

What is taxonomy?

The organization, classification, and naming of living things

Who originated the formal system of taxonomy?

Carl von Linné (carl linnaeus), 1701-1778

What is classification?

The orderly arrangement of organisms into groups

What is nomenclature?

The assignment of names to organisms

What is identification?

Determining and recording traits to place organisms in taxonomic schemes

What are the taxonomic levels from broadest to narrowest?

Domain, Kingdom, Phylum/Division,Class, Order, Family, Genus, Species

What are the three Domains of Life?

Bacteria, Archaea, and Eukarya

What are Bacteria?

The domain containing true bacteria

What are Archaea?

Organisms often associated with extreme environments such as high salt or heat

What is Eukarya?

The domain whose organisms have nuclei and membrane-bound organelles

What is binomial nomenclature?

A system that gives each organism two scientific names: genus and species

How is the genus written in a scientific name?

Capatalized

How is the species name written?

Lowercase

How are genus and species formatted?

Both italicized or underlined when handwritten

How can Staphylococcus aureus be abbreviated?

S. aureus

What is the difference between Bacteria and Archaea in the Three Domains?

Bacteria are true bacteria; Archaea are distinct organisms often found in extreme environments

What is the difference between Archaea and Eukarya?

Archaea lack the eukaryotic nucleus; Eukarya have nuclei and membrane-bound organelles

What is a host?

An organism that a parasite lives on or in

Why are microorganisms important to life?

Many are beneficial and some are essential for life

What are microbes used for in biotechnology?

They can produce useful products such as foods, drugs, vaccines, and energy sources

What does epidemiology focus on?

The monitoring and control of disease spread in populations

Why is aseptic technique important?

It reduces microbial contamination and help prevent infections

What major concept connects Jenner’s work to the scientific method?

Observation → hypothesis → experiment → results - reproductibility