MICR 2050 CHAPTER 1 - ABERCROMBIE

T/F: Only two of the main types of microorganisms are found in or on the normal healthy human body.

False Explanation: Bacteria, fungi, protozoans, archaea, and even viruses have been found as part of the human microbiome.

T/F: Genetic engineering has been done on microbes and plants, but not on animals.

False Explanation: Genetic engineering has been done on microbes, plants, and animals. Animal examples include the pigs that produce human hemoglobin and transgenic mice used in research.

T/F: There are many different sterile environments in planet Earth.

False Explanation: Sterile refers to an environment without ANY life forms, and because microorganisms are ubiquitous, there are almost no environments that would be considered sterile.

Who was Robert Hooke?

-1664 -English naturalist and architect -may have been the first to see microorganisms -coined the word "cell" to describe what he saw while viewing tree bark from a cork oak

Who was Francesco Redi?

-1668 -Italian natural philosopher -uncovered dishes of meat filled with maggots -covered dishes of meat attracted flies, but maggots formed on the gauze, not the meat -disproved spontaneous generation of maggots

Who was Antonie van Leeuwenhoek?

-1684 -Dutch fabric merchant -first person to accurately describe living microbes -used a simple microscope (one lens) -termed microbes "animalcules" -invented his own microscope to be able to thread count -looked at plaque from his teeth and saw things growing on them

Who was Oliver Wendell Holmes?

-1834 -American physician -Observed the apparent spread of puerperal fever (Streptococcus) by health care providers -published findings with guidelines to reduce transmission -this work was done before the germ theory of disease was developed

Who was Louis Pasteur?

-1864 -French microbiologist -father of microbiology -used swan-necked flasks -hay in flask -boiled it vigorously which kills the microbes -blue became cloudy; pink did not -disproved spontaneous generation -was contacted by wine producers because wine was going sour -he thought that the wine was "infected" with detrimental microbes and briefly heated the wine to kill these microbes (60°C, 30 min) -advent of pasteurization -also postulated that if wine can be infected by microbes, people can too (beginning of the germ theory of disease)

Who was Joseph Lister?

-1867 -British surgeon -applied germ theory to the treatment and prevention of disease -used carbolic acid (phenol) to clean hands, wounds, and operating rooms -number of post-operative infections was reduced -decreased surgical mortality by 15% -initiated the use of aseptic techniques to surgery (keeping a sterile field)

Who was John Tyndall?

-1876 -English physicist -described heat-resistant microbes from hay infusions -discontinuous heating used to sterilize -inactive but their DNA is there -endospores discovered

Who was Carl Woese?

-1975 -used 16S rRNA -three "Domains": archaea (all microbes), bacteria (all microbes), eukarya (some microbes)

Who was Aristotle?

-400 BC -favored spontaneous generation -philosopher and early naturalist -made detailed observations of nature -concluded that aphids, fleas, flies, and even mice could spontaneously form from other organic materials

How do you name organisms?

-Genus species (italicized)

Who was Robert Koch?

-German microbiologist -contemporary of Pasteur -worked on anthrax, tuberculosis, and cholera -used pure cultures (initiated the use of agar - type of seaweed) -further developed the germ theory of disease -described several postulates for proving the etiological (causative) agent of disease (1884) -boil agar = liquid; cool down = solid -before they used agar, they used gelatin

Who was Ignaz Semmelweis?

-Hungarian physician - "Saviour of Mothers" -1840's - hand disinfection prevented transfer of infections -higher rates of infection in maternity wards attended by doctors than midwives -hand washing by doctors prior to attending maternity patients decreased mortality -he noticed that midwives washed their hands more and doctors rarely washed their hands -placed in an insane asylum, beat, and died 14 days later because he got infections from the beatings

Levels of Taxonomy

-Kingdom -Phylum -Class/Domain -Order -Family -Genus -Species

Germ Theory

-Pasteur: microbes cause disease -Koch: a specific bacillus (Bacillus anthracis) caused anthrax disease aka specific organisms cause specific diseases -Koch's postulates: set of rules for establishing that a specific organism causes a specific disease

Of the major groups of microorganisms, which are eukaryotes?

-algae -protozoa -helminths -fungi

What are the 6 major groups of microorganisms?

-bacteria/archaea -algae -protozoa -helminths -fungi -viruses: noncellular, parasitic, protein-coated genetic elements

Who was Carl von Linné?

-he used taxonomy and began systematically classifying living things (all he know was what he could see

Microbiology Branches of Study

-medical microbiology -public health microbiology and epidemiology (study of the incident spread and control of diseases) -immunology -industrial microbiology -agricultural microbiology (study of microbes that affect plants) -environmental microbiology

Importance of Microbes

-microbes are the earliest organisms found in the fossil record (driving force behind the development of our atmosphere) -they perform essential reactions in the environment -microbes can be harnessed to work for us -they sometimes cause infectious diseases (about 2,000) -bacteria are ubiquitous (everywhere)

Microbial Disease

-some microbes cause infectious diseases -only a few percent of all microbes are associated with disease

What is the definition of microbiology?

-study of small living things -working definition: study of entities too small to be seen with the unaided human eye (<.2 mm = 200 μm = 200,000 nm)

What are Koch's postulates?

-the same pathogen must be present in every case of the disease -the pathogen must be isolated from the diseased host and grown in pure culture -the pathogen from the pure culture must cause the disease when it is inoculated into a healthy, susceptible laboratory animal -the pathogen must be isolated from the inoculated animal and must be shown to be the original organism

Order the following choices to reflect the relative sizes of microorganisms as compared to each other and other cells, ranging from the largest to the smallest. -red blood cell -viruses -reproductive structure of bread mold -most bacteria

1. reproductive structure of bread mold 2. red blood cell 3. most bacteria 4. viruses Explanation: Remember microbes are small that they must be viewed through a microscope except for a few colonial forms. Bacteria usually range from 1 to 10mm in size and are larger than viruses. Figure 1.6 is very helpful in depicting the relative sizes of different cells.

T/F: Not all eukaryotes are microorganisms.

True

T/F: Human proteins, such as insulin and hemoglobin, can be produced by yeast or bacteria.

True Explanation: Human genes can be cut and spliced into vectors that deliver the DNA to yeast or bacteria. These hosts then produce the protein coded by the gene. Insulin was the first therapeutic drug manufactured in this way back in the early 1980s.

T/F: Most microorganisms that are found in and on humans do not cause harm and can sometimes benefit the host.

True Explanation: Most microorganisms associated with the human host (the human microbiome) do not cause disease and actually benefit the host with their presence.

T/F: Swabbing the surface of your skin anywhere on your body and culturing that sample in the lab is likely to result in the growth of millions of bacterial cells on the culture plate, even if you practice good hygiene.

True Explanation: Our own human cells are outnumbered 10 to 1 by microbial cells, so it is very likely that a swab sample from even clean skin would contain millions of bacterial cells.

T/F: Photosynthetic microorganisms contribute more oxygen to the atmosphere than plants.

True Explanation: Photosynthetic microorganisms (bacteria and algae) produce the majority of oxygen found in the atmosphere and are responsible for more than 70% of photosynthesis on earth.

Who established the four postulates to verify the germ theory and developed many of the laboratory techniques still used in microbiology labs today? a. Koch b. Hooke c. Pasteur d. Lister

a. Koch

Who cultured microbes in swan-necked flasks? a. Louis Pasteur b. Francesco Redi c. Schultze and Schwann

a. Louis Pasteur

Which of the following choices is a correct way to denote the binomial name of a microorganism? a. Staphylococcus aureus (italicized) b. Staphylococcus aureus (not italicized) c. staphylococcus Aureus (italicized) d. staphylococcus aureus (italicized) e. Staphylococcus Aureus (italicized)

a. Staphylococcus aureus (italicized) Explanation: The binomial, or scientific name, of a microorganism includes the genus name followed by the species name. It must be typed in italics or underlined if handwritten. In addition, the first letter of the genus must be capitalized while the first letter of the species name is lowercase.

Which cellular microbes don't have a nucleus? a. bacteria b. fungi c. protozoans d. helminths e. algae

a. bacteria Explanation: Of all the cellular microorganisms, only bacteria and archaea lack a nucleus.

Cellular microbes include which of the following. a. bacteria b. fungi (hint: eukaryotes involved in decomposition) c. protozoans (hint: single-celled eukaryotes) d. viruses e. helminths (hint: term designating all parasitic worms) f. algae (hint: photosynthetic plantlike organisms)

a. bacteria b. fungi (hint: eukaryotes involved in decomposition) c. protozoans (hint: single-celled eukaryotes) e. helminths (hint: term designating all parasitic worms) f. algae (hint: photosynthetic plantlike organisms)

Al _____ are microorganisms, but not all _____ are microorganisms. a. bacteria; eukaryotes b. eukaryotes; bactera

a. bacteria; eukaryotes

Which of the following is an example of a biofilm commonly found in the human body? a. dental plaque b. salivary secretions c. ear wax d. yellow or green discharge

a. dental plaque Explanation: Dental plaque is a biofilm on the surface of your teeth!

Which of the following are examples of biotechnology? a. development of biofuels b. biofilm production c. beer and wine production d. recombinant DNA technology e. bioremediation

a. development of biofuels c. beer and win production d. recombinant DNA technology e. bioremediation Explanation: Biotechnology involves any use of microorganisms or their products for human benefit. Biofilms are formed by microorganisms but they are not used for human benefit.

The scientific name of a microorganism is a combination of the _____ name, which is capitalized, followed by the _____ name, which begins with a lower case letter. a. genus; species b. phylum; genus c. species; genus d. genus; kingdom

a. genus; species Explanation: The method of assigning the scientific name is called the binomial system of nomenclature and is a combination of the genus followed by the species name. An example is Escherichia coli where Escherichia is the genus and coli is the species.

Choose all that apply to virus. a. must be viewed with an electron microscope b. size range: 1-10μm c. cell type that lacks a nucleus d. contains a nucleus and other membrane-bound organelles e. acellular particles f. size range: 10-200nm

a. must be viewed with an electron microscope e. acellular particles f. size range: 10-200nm Explanation: Viruses are nonliving particles and usually are only nanometers in size so they require an electron microscope for viewing.

Which process uses the sun's energy to produce organic compounds and ATP from carbon dioxide and water? a. photosynthesis b. bioremediation c. respiration

a. photosynthesis

Who covered meat with gauze to prevent flies from landing on it? a. Louis Pasteur b. Francesco Redi c. Schultze and Schwann

b. Francesco Redi

Who established the four postulates to verify the germ theory and developed many of the laboratory techniques still used in microbiology labs today? a. Lister b. Koch c. Pasteur d. Hooke

b. Koch

Which type(s) of microorganisms have cells that do NOT contain organelles? a. yeast b. archaea c. protists d. bacteria

b. archaea d. bacteria

Microorganisms have adapted to nearly every environment through the process of ______. a. bioremediation b. evolution c. ubiquity d. recombinant DNA technology

b. evolution Explanation: Microbes have adapted to environmental conditions through tiny gradual changes over billions of years. This process is called evolution.

Which cellular microbes have a nucleus? a. bacteria b. fungi c. protozoans d. helminths e. algae

b. fungi c. protozoans d. helminths e. algae

The microorganisms that live in or on the human body are called the ______. a. archaea b. microbiome c. prokaryotes d. recombinants

b. microbiome Explanation: All of the microbes in a certain environment are called the microbiome.

Choose all that apply to bacteria. a. must be viewed with an electron microscope b. size range: 1-10μm c. cell type that lacks a nucleus d. contains a nucleus and other membrane-bound organelles e. acellular particles f. size range: 10-200nm

b. size range: 1-10μm c. cell type that lacks a nucleus Explanation: Bacteria are larger than viruses, falling into the micrometer range. They are cells without a nucleus.

Who passed air through chemicals or glass tubes before treating infusions? a. Louis Pasteur b. Francesco Redi c. Schultze and Schwann

c. Schultze and Schwann

Why are biofilms important in infectious disease? a. the secreted extracellular "gunk" is highly damaging to tissues b. most microbes cannot cause disease without other microbes present c. bacteria in biofilms are often protected from antibiotics

c. bacteria in biofilms are often protected from antibiotics Explanation: Antibiotics are often blocked by the protective coating found in biofilms. Also, bacteria may express different genes when they are part of a biofilm and become less susceptible to antimicrobial drugs.

Which of the following is the study of the factors affecting the prevalence and spread of disease within a community? a. geomicrobiology b. immunology c. epidemiology

c. epidemiology

The cells of which microorganisms contain organelles? a. bacteria b. archaea c. eukaryotes

c. eukaryotes

Which microbe(s) have a true nucleus? a. prion b. virus c. protists d. yeast e. archaea

c. protists d. yeast

What 20th century discovery has been instrumental to the field of genetic engineering by allowing researchers to cut and splice specific DNA fragments into microorganism? a. the microbiome b. ribozymes c. restriction enzymes d. small RNAs

c. restriction enzymes Explanation: Restriction enzymes, discovered in the 1970s, allow researchers to cut DNA at specific places and insert those pieces into vectors that deliver the DNA to other cells.

Microbes can be used for bioremediation such as...

cleaning up after an oil spill

Select the individual below that ground glass lenses to very fine specifications so that he was able to develop a microscope for observing and describing living microscopic animalcules. a. Louis Pasteur b. Robert Meischer c. Gregor Mendel d. Antonie van Leeuwenhoek

d. Antonie van Leeuwenhoek Explanation: Antonie van Leeuwenhoek developed the first glass lenses, taking the initial step into the field of microscopy.

What is a biofilm? a. a bacterial cell that secretes an extensive network of fibers around its cell wall b. free-floating bacteria that move through the blood to other sites c. a layer of sugars that persist even after bacteria have been killed by antibiotics d. a group of bacteria that accumulate in layers and secrete protective extracellular material

d. a group of bacteria that accumulate in layers and secrete protective extracellular material Explanation: Bacteria attach to a surface and excrete a sticky extracellular substance. Other species can be recruited to the biofilm, and the result is layers of multiple species of bacterial surrounded by a protective coating.

Which microbe(s) do NOT have a true nucleus? a. algae b. protozoa c. yeast d. bacteria

d. bacteria

Choose all that apply to eukaryotes. a. must be viewed with an electron microscope b. size range: 1-10μm c. cell type that lacks a nucleus d. contains a nucleus and other membrane-bound organelles e. acellular particles f. size range: 10-200nm

d. contains a nucleus and other membrane-bound organelles Explanation: Eukaryotes have a nucleus and are larger than both viruses and bacteria. An example is the helminths.

The major groups of microorganisms studied by microbiologists include bacteria and archaea, algae, helminths, protozoans, viruses, and _______. a. spores b. cysts c. arthropods d. fungi

d. fungi Explanation: Fungi are included in the major groups of microorganisms studied by microbiologists.

Noncellular microbes include which of the following. a. bacteria b. fungi (hint: eukaryotes involved in decomposition) c. protozoans (hint: single-celled eukaryotes) d. viruses e. helminths (hint: term designating all parasitic worms) f. algae (hint: photosynthetic plantlike organisms)

d. viruses (also doesn't have a nucleus) Explanation: All non-cellular microbes, such as viruses or prions, lack a nucleus.

Microbes are essential for _____ of dead organisms.

decomposition

The papers that Pasteur published regarding the germ theory of _____ and disproving the _____ _____ _____ _____ were read by his contemporary Joseph Lister, a surgeon battling high post-surgical mortality in his patients.

disease; theory of spontaneous generation

Public health microbiology and _____ focus on the analysis of factors affecting the prevalence and spread of disease within a community.

epidemiology

Lister had studied inflammation and suspected that wound sepsis was caused by an infection agent in the air. Pasteur's work solidified his _____ so he began to use _____ before performing an operation, drastically reducing the number of deaths in patients following surgery.

hypotheses; phenol

_____ is the study of the system of body defenses, which protect it against infection.

immunology

Microbes can produce important compounds such as...

insulin, antibiotics, MSG, ethanol

What is the definition of spontaneous generation (abiogenesis)?

life rapidly appears from non-living things

What is the definition of biogenesis?

living things originate from other living things

In 1857, Louis Pasteur discovered that specific organisms carry out chemical reactions and create _____ end-products such as alcohol and lactic acid.

metabolic

_____ is a specialized area of biology that deals with living things ordinarily too small to be seen without magnification.

microbiology

Microbial photosynthesis account for most of the atmospheric _____ on Earth (70%).

oxygen

Pasteur is also credited with the process of _____ which removes pathogens from consumable liquids, reducing _____ and subsequent illness.

pasteurization; contamination

_____ is the light-fueled conversion of carbon dioxide to organic material.

photosynthesis

What is the definition of phycology?

study of algae

What is the definition of mycology?

study of fungi

What is the definition of bacteriology?

study of prokaryotes

What is the definition of protozoology?

study of protozoa

What is the definition of immunology?

study of the immune system

What is the definition of virology?

study of viruses

Many biologically important elements (such as _____, _____, _____) are cycled by microbes.

sulfur, nitrogen, phosphorous

What is the definition of taxonomy?

the science of classifying living things

If you study HIV, what sort of microbiologist would you be considered?

virologist

Microbes can be used to make or preserve food products such as...

yogurt, salami, beer, wine, cheeses