Chapter 1: The Microbial World and You

List the three domains.

- Bacteria - Archaea - Eukarya

Differentiate the major characteristics of each group of microorganisms.

- Bacteria (cell walls contain a protein-carbohydrate complex called peptidoglycan) - Archaea ( cell walls, if present, lack peptidoglycan) - Eukarya, which includes the following: -- Protists (slime molds, protozoa, and algae) -- Fungi ( unicellular yeasts, multicellular molds, and mushrooms) -- Plants (mosses, ferns, conifers, and flowering plants) -- Animals (sponges, worms, insects, and vertebrates)

Types of Microorganisms

- Bacteria are unicellular organisms. Because they have no nucleus, the cells are described as prokaryotic. - The three major basic shapes of bacteria are bacillus, coccus, and spiral. - Most bacteria have a peptidoglycan cell wall; they divide by binary fission, and they may possess flagella. - Bacteria can use a wide range of chemical substances for their nutrition. - Archaea consist of prokaryotic cells; they lack peptidoglycan in their cell walls. - Archaea include methanogens, extreme halophiles, and extreme thermophiles. - Fungi (mushrooms, molds, and yeast) have eukaryotic cells (cells with a true nucleus). - Most fungi are multicellular. - Fungi obtain nutrients by absorbing organic material from their environment. - Protozoa are unicellular eukaryotes. - Protozoa obtain nutrients by absorption or ingestion through specialized structures. - Algae are unicellular or multicellular eukaryotes that obtain nutrients by photosynthesis. - Algae produce oxygen and carbohydrates that are used by other organisms. - Viruses are non-cellular entities that are parasites of cells. - Viruses consist of a nucleic acid core (DNA or RNA) surrounded by a protein coat. An envelope may surround the coat. - The principal groups of multicellular animal parasites are flatworms and roundworms, collectively called helminths. - The microscopic stages in the life cycle of helminths are identified by traditional microbial procedures.

Modern Developments in Microbiology

- Bacteriology is the study of bacteria, mycology is the study of fungi, and parasitology is the study of parasitic protozoa and worms. - Microbiologists are using genomics, the study of all of an organism's genes, to classify bacteria, fungi, and protozoa. - The study of AIDS, analysis of the action of interferons, and the development of new vaccines are among the current research interests in immunology. - New techniques in molecular biology and electron microscopy have provided tools for advancing our knowledge of virology. - The development of recombinant DNA technology has helped advance all areas of microbiology.

The Birth of the Modern Chemotherapy: Dreams of a "Magic Bullet"

- Chemotherapy is the chemical treatment of a disease. - Two types of chemotherapeutic agents are synthetic drugs (chemically prepared in the laboratory) and antibiotics (substances produced Naturally by bacteria and fungi to inhibit the growth of other microorganisms). - Paul Ehrlich introduced an arsenic-containing chemical called salvarsan to treat syphilis (1910). Alexander Fleming observed that the penicillin fungus inhibited the growth of a bacterial culture. He named the active ingredient penicillin (1928). - Penicillin has been used clinically as an antibiotic since the 1940s. - Researchers are tackling the problem of drug-resistant microbes.

Microbes and Human Disease

- Everyone has microorganisms in and on the body; these make up the normal microbiota, or flora. - The disease-producing properties of a species of microbe and the host's resistance are important factors in determining whether a person will contract a disease. - Bacterial communities that form slimy layers on surfaces are called biofilms. - An infectious disease is one in which pathogens invade a susceptible host. - An emerging infectious disease (EID) is a new or changing disease showing an increase in incidence in the recent past or a potential to increase in the near future.

Naming and Classifying Microorganisms: Nomenclature

- In a nomenclature system designed by Carolus Linnaeus (1735), each living organism is assigned two names. - The two names consist of a genus and a specific epithet, both of which are underlined or italicized.

Microbes in Our Lives

- Living things too small to be seen with the unaided eye are called microorganisms. - Microorganisms are important in maintaining Earth's ecological balance. - Some microorganisms live in humans and other animals and are needed to maintain good health. - Some microorganisms are used to produce food and chemicals. - Some microorganisms cause disease.

Microbes and Human Welfare

- Microorganisms degrade dead plants and animals and recycle chemical elements to be used by living plants and animals. - Bacteria are used to decompose organic matter in sewage. - Bioremediation processes use bacteria to clean up toxic wastes. - Bacteria that cause diseases in insects are being used as biological controls of insect pests. Biological controls are specific for the past and do not harm the environment. - Using microbes to make products such as foods and chemicals is called biotechnology. - Using recombinant DNA, bacteria can produce important substances such as proteins, vaccines, and enzymes. - In gene therapy, viruses are used to carry replacements for defective or missing genes into human cells. - Genetically modified bacteria are used in agriculture to protect plants from frost and insects and to improve the shelf life of produce.

Identify the contributions to microbiology made by Needham, Spallanzani, Virchow, and Pasteur.

- Needham performed a broth experiment to prove the theory of spontaneous generation. - Spallanzani corrected Needham's broth experiment to disprove spontaneous generation. - Virchow proposed the theory of biogenesis. - Pasteur created aseptic techniques that are now used in hospitals and labs everywhere.

List at least four beneficial activities of microorganisms.

- Recycling vital element - Sewage treatment - using microbes to recycle water - Bioremediation - using microbes to clean up pollutants - Insect pest control by microorganisms

A Brief History of Microbiology: The First Observations

- Robert Hooke observed that cork was composed of "little boxes"; he introduced the term cell (1665). - Hooke's observations laid the groundwork for development of the cell theory, the concept that all living things are composed of cells. - Anton van Leeuwenhoek, using a simple microscope, was the first to observe microorganisms (1673).

Explain the importance of the observations made by Hooke and van Leeuwenhoek.

- Robert Hooke reported to the world that life's smallest structural units were "little boxes", or "cells", as he called them. Using his improved version of a compound microscope (one that uses two sets of lenses), Hooke was able to see individual cells. Hooke's discovery marked the beginning of the cell theory. - Anton van Leeuwenhoek was probably the first actually to observe live microorganisms through the magnifying lenses of more than 400 microscopes he constructed. Leeuwenhoek made detailed drawings of "animalcules" he found in rainwater, in his own feces, and in material scraped from his teeth. These drawings have since been identified as representations of bacteria and protozoa.

The Golden Age of Microbiology

- The science of microbiology advanced rapidly between 1857 and 1914. - Pasteur found that yeast ferment sugars to alcohol and that bacteria can oxide the alcohol to acetic acid. - A heating process called pasteurization is used to kill bacteria in some alcoholic beverages and milk. - Agostino Bassi (1835) and Pasteur (1865) showed a casual relationship between microorganisms and disease. - Joseph Lister introduced the use of a disinfectant to clean surgical wounds in order to control infections in humans (1860s). - Robert Koch proved that microorganisms cause disease. He used a sequence of procedures, now called Koch's postulates (1876) that are used today to prove that a particular organism causes a particular disease. - In a vaccination, immunity (resistance to a particular disease) is conferred by inoculation with a vaccine. - In 1798, Edward Jenner demonstrated that inoculation with cowpox material provides humans with immunity to smallpox. - About 1880, Pasteur discovered that a virulent bacteria could be used as a vaccine for fowl cholera; he coined the word vaccine. - Modern vaccines are prepared from living avirulent microorganisms or killed pathogens, from isolated components of pathogens, and by recombinant DNA techniques.

The Debate over Spontaneous Generation

- Until the mid-1880s, many people believed in spontaneous generation, the idea that living organisms could arise from nonliving matter. - Francesco Redi demonstrated that maggots appear on decaying meat only when flies are able to lay eggs on the meat (1668). - John Needham claimed that microorganisms could arise spontaneously from heated nutrient broth (1745). - Lazaro Spallanzani repeated Needham's experiment and suggested that Needham's results were due to microorganisms in the air entering his brotj (1765). - Rudolph Virchow introduced the concept of biogenesis; living cells can arise only from pre-existing cells (1858). - Louis Pasteur demonstrated that microorganisms are in the air everywhere and offered proof of biogenesis (1861). - Pasteur's discoveries led to the development of aseptic techniques used in laboratory and medical procedures to prevent contamination by microorganisms.

Quizzes and Pretests

@ Mastering Microbiology

Recombinant DNA

A DNA molecule produced by combining DNA from two different sources

Eukaryotes

A cell having DNA inside a distinct membrane-enclosed nucleus

Prokaryotes

A cell whose genetic material is not enclosed in a nuclear envelope

Synthetic Drugs

A chemotherapeutic agent that is prepared from chemicals in a laboratory

Distinguish a genus from a specific epithet.

A genus is capitalized; a specific epithet is NOT capitalized.

Microbes

A living organism too small to be seen with the naked eye; includes bacteria, fungi, protozoa, and microscopic algae, also includes viruses; also known as microorganism

List several ways in which microbes affect our lives.

A majority of microbes help maintain the balance of living organisms and chemicals in our environment. Marine and freshwater microorganisms form the basis of the food chain in oceans, lakes, and rivers. Soil lmicrobes help break down wastes and incorporate nitrogen gas from the air into organic compounds, thereby recycling chemical elements between the soil, water, life, and air. Certain microbes play important roles in photosynthesis, a food -and oxygen-generating process that is critical to life on Earth. Humans and many other animals depend on the microbes in their intestines for the digestion and synthesis of some vitamins that their bodies require, including some B Vitamins for metabolism and Vitamin K for blood clotting. Microorganisms are used in the synthesis of chemical products such as vitamins, organic acids, enzymes, alcohols, and many drugs. Microbes are used to produce acetone and butanol, and the vitamins B2 and B12. The food industry also uses microbes in producing vinegar, sauerkraut, pickles, soy sauce, cheese, yogurt, bread, and alcoholic beverages. Though only a minority of microorganisms are pathogenic (disease causing), practical knowledge of microbes is necessary for medicine and the related health sciences.

Pathogenic

A medical term that describes viruses, bacteria, and other types of germs that can cause some kind of disease

Biofilm

A microbial community that usually forms as a slimmy layer on a surface

Define biofilm.

A microbial community that usually forms as a slimy layer on a surface.

Emerging Infectious Diseases

A new or changing disease that is increasing or has the potential to increase in incidence in the near future

Define emerging infectious disease.

A new or changing disease that is increasing or has the potential to increase in incidence in the near future.

Helminths

A parasitic roundworm or flatworm

Algae

A photosynthetic eukaryote; may be unicellular, filamentous, or multicellular but lack the tissues found in plants

Microbial Genetics

A subject area within microbiology and genetic engineering. It studies the genetics of very small (micro) organisms; bacteria, archaea, viruses and some protozoa and fungi

Viruses

A submicroscopic, parasitic, filterable agent consisting of a nucleic acid surrounded by a protein coat

Which microorganism is best described by "cell wall made of cellulose; photosynthetic"?

Algae

Cell Theory

All living organisms are composed of cells and arise from pre-existing cells

Which of the following is a beneficial activity of microorganisms? a. Some microorganisms are used as food for humans. b. Some microorganisms use carbon dioxide. c. Some microorganisms provide nitrogen for plant growth. d. Some microorganisms are used in sewage treatment processes. e. All of the above

All of the above

Classifications of Microorganisms

All organisms are classified into - Bacteria - Archaea - Eukarya Eukarya include protists, fungi, plants, and animals.

Microbial Ecology

Also known as environmental microbiology, is the ecology of microorganisms: their relationship with one another and with their environment. It concerns the three major domains of life—Eukaryota, Archaea, and Bacteria—as well as viruses. Microorganisms, by their omnipresence, impact the entire biosphere.

Antibiotics

An antimicrobial agent, usually produced naturally by a bacterium or fungus

Fungi

An organism that belongs to the Kingdom fungi, a eukaryotic absorptive chemoheterotroph

Which microorganism is best described by "prokaryote without peptidoglycan cell wall"?

Archaea

Who proved that DNA is the hereditary material?

Avery, MacLeod, and McCarty

What type of microorganism has a peptidoglycan cell wall, has DNA that is not contained in a nucleus, and has flagella?

Bacteria

Which microorganism is best described by "cell wall made of peptidoglycan"?

Bacteria

Which group of microbes are prokaryotes? Which are eukaryotes?

Bacteria and Archaea are prokaryotes (pre-nucleus) genetic material is not enclosed inside a nucleus. Fungi, Protozoa, and Algae, are eukaryotes, organisms whose cells have a distinct nucleus containing the cell's genetic material (DNA), surrounded by a special envelope called a nuclear membrane.

What are the three domains?

Bacteria, Archaea, and Eukarya

Define bacteriology, mycology, parasitology, immunology, and virology.

Bacteriology is the study of bacteria, mycology is the study of fungi, parasitology is the study of parasitic protozoa and worms, immunology is the study of immunity, and virology is the study of viruses.

Who showed that genes code for enzymes?

Beadle and Tatum

Who spliced animal DNA to bacterial DNA?

Berg

Briefly state the role microorganisms play in biofilms.

Biofilms are aggregated bacteria adhering to each other and to a solid surface.

Into which field of microbiology would the following scientists best fit? Researcher who studies biodegrade in of toxic wastes a. Biotechnology b. Immunology c. Microbial ecology d. Microbial genetics e. Microbial physiology f. Molecular biology g. Mycology h. Virology

Biotechnology and Microbial ecology

Differentiate biotechnology from recombinant DNA technology.

Biotechnology is the industrial application of microorganisms, cells, or cell components to make a useful product. Recombinant DNA technology is manufacturing and manipulating genetic material in vitro; also called genetic engineering.

Into which field of microbiology would the following scientists best fit? Researcher who studies the production of human proteins by bacteria a. Biotechnology b. Immunology c. Microbial ecology d. Microbial genetics e. Microbial physiology f. Molecular biology g. Mycology h. Virology

Biotechnology, Microbial genetics, and Microbial physiology

Briefly state the role microorganisms play in recycling of elements.

Carbon, oxygen, nitrogen, sulfur, and phosphorus are required for all living organisms. Microorganisms convert these elements into forms that are useful for other organisms. Many bacteria decompose material and release carbon dioxide into the atmosphere, which plants use. Some bacteria can take nitrogen from the atmosphere and convert it into a form that plants and other microorganisms can use.

What is the cell theory?

Cell theory is the theory that all living things are composed of cells.

Briefly state the role microorganisms play in biological control of pests.

Certain microorganisms cause diseases in insects. Microorganisms that kill insects can be effective biological control agents because they are specific for the pest and do not persist in the environment.

Koch's Postulates

Criteria used to determine the causative agent of infectious diseases

Archaea

Domain of prokaryotic cells lacking peptidoglycan; one of the three domains

Bacteria

Domain of prokaryotic organisms, characterized by peptidoglycan cell walls

Which of the following statements about E. coli is false? a. E. coli was the first disease-causing bacterium identified by Koch. b. E. coli is part of the normal microbiota of humans. c. E. coli is beneficial in human intestines. d. A disease-causing strain of E. coli causes bloody diarrhea. e. None of the above

E. coli was the first disease-causing bacterium identified by Koch.

Who used the first synthetic chemotherapeutic agent?

Ehrlich

Identify the contributions to microbiology made by Ehrlich and Fleming.

Ehrlich found the arsenic-based medication Salvarsan used to treat syphilis. Fleming discovered Penicillium.

What was Ehrlich's "Magic Bullet"?

Ehrlich's "Magic Bullet" was a substance that could destroy a pathogen without harming the host.

The genus name of a bacterium is "erwinia", and the specific epithet is "amylovora." Write the scientific name of this organism correctly. Using this name as an example, explain how scientific names are chosen.

Erwinia amylovora (italicized) is the correct way to write this scientific name. Scientific names can be derived from the names of scientists. In this case, Erwinia is derived from Erwin F. Smith, and American plant pathologist. Scientific names also can describe the organism, its habitat, or it's niche. E. amylovora is a pathogen of plants (amylo- = starch; vora = eat)

Who discovered penicillin?

Fleming

How was spontaneous generation disproved?

Francesco Redi set out in 1668 to demonstrate that maggots did not arise spontaneously from decaying meat. Redi filled two jars with decaying meat. The first was left unsealed, the flies laid their eggs on the meat, and the eggs developed into larvae. The second jar was sealed, and because the flies could not lay their eggs on the meat, no maggots appeared. Still, Redi's antagonists were not convinced, they claimed that fresh air was needed for spontaneous generation. So Redi set up a second experiment, in which he covered a jar with a fine net instead of sealing it. No larvae appeared in the gauze covered jar, even though air was present. Maggots appeared only when flies were allowed to leave their eggs on the meat.

Which microorganism is best described by "cell walls made of chitin"?

Fungi

Which microorganism is best described by "multicellular animals"?

Helminths

What is the significance of Jenner's discovery?

His discovery led to the eradication of smallpox around the world.

Who was the first to observe cells in plant material and name them?

Hooke

Into which field of microbiology would the following scientists best fit? Researcher who studies the symptoms of AIDS a. Biotechnology b. Immunology c. Microbial ecology d. Microbial genetics e. Microbial physiology f. Molecular biology g. Mycology h. Virology

Immunology

Who observed that viruses are filterable?

Iwanowski

Who discovered how DNA controls protein synthesis in a cell?

Jacob and Monod

Who developed a vaccine against smallpox?

Jenner

Identify the importance of Jenner's work.

Jenner explored inoculations and immunity by treating humans with cowpox virus so that they would be immune to smallpox.

Who proved that microorganisms can cause disease?

Koch

What is the importance of Koch's postulates?

Koch discovered bacillus anthrasis and proved that specific microbes cause specific diseases 1. The causative agent must be isolated in every case of the disease. 2. The causative agent must be cultured outside the host. 3. When injected into a healthy, susceptible host, the host must get the disease. 4. The same etiologic agent must be cultured from the once healthy host when it becomes sick.

Identify the importance of Koch's postulates.

Koch's postulates are four criteria designed in the 1880s to establish a casual relationship between a causative microbe and a disease. Koch's postulates are the following: - The causative agent must be isolated in every case of the disease. - The causative agent must be cultured outside the host. - When introduced into a healthy, susceptible host, the host must get the disease. - The same etiologic agent must be cultured from the once healthy host when it becomes sick.

Aseptic Techniques

Laboratory techniques used to minimize contamination

Who proposed a classification system for streptococci based on antigens in their cell walls?

Lancefield

Who discovered that DNA can be transferred from one bacterium to another?

Lederberg and Tatum

Who was the first to use disinfectants in surgical procedures?

Lister

Which of the following statements is the best definition of biogenesis? a. Nonliving matter gives rise to living organisms. b. Living cells can only arise from pre-existing cells. c. A vital force is necessary for life. d. Air is necessary for living organisms. e. Microorganisms can be generated from nonliving matter.

Living cells can only arise from pre-existing cells.

Recombinant DNA Technology

Manufacturing in manipulating genetic material in vitro, also called genetic engineering

Briefly state the role microorganisms play in sewage treatment.

Matter in sewage is decomposed by bacteria into carbon dioxide, nitrates, phosphates, sulfate, and other inorganic compounds in a wastewater treatment plant.

Into which field of microbiology would the following scientists best fit? Researcher who studies the life cycle of Cryptosporidium a. Biotechnology b. Immunology c. Microbial ecology d. Microbial genetics e. Microbial physiology f. Molecular biology g. Mycology h. Virology

Microbial ecology

Into which field of microbiology would the following scientists best fit? Researcher who develops gene therapy for a disease a. Biotechnology b. Immunology c. Microbial ecology d. Microbial genetics e. Microbial physiology f. Molecular biology g. Mycology h. Virology

Microbial genetics

Differentiate microbial genetics from molecular biology.

Microbial genetics studies the mechanisms of how microorganisms inherit traits. Molecullar biology studies how genetic information is carried in molecules of DNA an how DNA directs the synthesis of proteins.

Into which field of microbiology would the following scientists best fit? Researcher who studies the production of toxins by E.coli a. Biotechnology b. Immunology c. Microbial ecology d. Microbial genetics e. Microbial physiology f. Molecular biology g. Mycology h. Virology

Microbial physiology

Define normal microbiota and resistance.

Microbiota, or normal flora, not only do us no harm, but also in some cases actually benefit us. For example, some normal microbiota protect us against disease by preventing the overgrowth of harmful microbes. Unfortunately, under some circumstances, normal microbiota can make us sick or infect people we contact. The distinction between health and disease is in large part a balance between the natural defenses of the body and the disease-producing properties of microorganisms. Whether our bodies overcome the offensive tactics of a particular microbe depends on our resistance - the ability to ward off disease.

Briefly state the role microorganisms play in vaccine production.

Microorganisms can be used as vaccines. Some microbes can be genetically modified to produce components of vaccines.

Which of the following is a scientific name? a. Mycobacterium tuberculosis b. Tubercle bacillus

Mycobacterium tuberculosis

Into which field of microbiology would the following scientists best fit? Researcher who studies the the fungus Candida albicans a. Biotechnology b. Immunology c. Microbial ecology d. Microbial genetics e. Microbial physiology f. Molecular biology g. Mycology h. Virology

Mycology

Briefly state the role microorganisms play in normal microbiota.

Normal microbiota are microorganisms that are found in and on the human body. They do not usually cause disease and can be beneficial.

Differentiate normal microbiota and infectious disease.

Normal microbiota are microorganisms that colonize a host without causing disease, also called normal flora. infectious disease is a disease in which pathogens invade a susceptible host and carry out at least part of their life cycle in the host.

Who discovered spontaneous generation?

Pasteur

Explain how Pasteur's work influenced Lister and Koch.

Pasteur's work on germ theory of disease and aseptic techniques influence Lister's study of using disinfectants to prevent the spread of disease in humans (washing hands between patients, etc.) His work also influence Koch's experiments that proved microorganisms caused disease and helped influence his development of postulates.

How did the idea of spontaneous generation come about?

People came to believe that living organisms arise from nonliving matter because they would see flies coming out of manure, maggots coming out of dead animals, and microorganisms appearing in liquids after a day or two.

Which microorganism is best described by "unicellular, complex cell structure lacking a cell wall"?

Protozoa

Briefly state the role microorganisms play in human insulin production.

Recombinant DNA techniques have resulted in insertion of the gene for insulin production into bacteria. These bacteria can produce human insulin inexpensively.

Describe some of the destructive and beneficial actions of microbes.

Some destructive actions of microbes include pathogenic and food spoilage. Some beneficial actions of microbes include soil microbes break down waste, photosynthesis, digestion and synthesis of vitamins, production of acetone, butanol, Vitamin B2 and Vitamin B12, and food production.

Spallanzani's conclusion about spontaneous generation was challenged because Lavoisier had just shown that oxygen was the vital component of air. Which of the following statements is true? a. All life requires air. b. Only disease-causing organisms require air. c. Some microbes do not require air. d. Pasteur kept air out of his biogenesis experiments. e. Lavoisier was mistaken.

Some microbes do not require air.

Compare spontaneous generation to biogenesis.

Spontaneous generation is the belief that some forms of life could arise spontaneously from nonliving matter. Biogenesis is the belief that living cells can arise only from pre-existing living cells.

Who was the first to characterize a virus?

Stanley

Immunity

State of being not susceptible to a particular disease

Resistance

The ability to ward off diseases through innate or adaptive immunity

What evidence supported spontaneous generation?

The case for spontaneous generation of microorganisms seemed to be strengthened in 1745, when John Needham, an Englishmen, found that even after he heated nutrient fluids (chicken broth and corn broth) before pouring them into covered flasks, the cooled solutions were soon teeming with microorganisms. Needham claimed that microbes developed spontaneously from the fluids. Twenty years later, Lazaro Spallanzani, an Italian scientist, suggested that microorganisms from the air probably had entered Needham's solutions after they were boiled. Spallanzani showed that nutrient fluids heated after being sealed in a flask did not develop microbial growth. Needham responded by claiming the "vital force" necessary for spontaneous generation had been destroyed by the heat and was kept out of the flask by the seals.

Fermentation

The enzymatic degradation of carbohydrates in which the final electron acceptor is an organic molecule, ATP is synthesized by substrate level phosphorylation, and O2 is not required

Genus

The first name of the scientific name (binomial)

Spontaneous Generation

The idea that life could arise spontaneously from nonliving matter

Biotechnology

The industrial application of microorganisms, cells, or cell components to make a useful product

Normal Microbiota

The microorganisms that colonize a host without causing disease, also called normal flora

Summarize in your own words the germ theory of disease.

The principle that microorganisms can cause diseases.

Germ Theory of Disease

The principle that microorganisms cause disease

Pasteurization

The process of mild heating to kill particular spoilage microorganisms are pathogens

Molecular Biology

The science dealing with DNA and protein synthesis of living organisms

Mycology

The scientific study of fungi

Parasitology

The scientific study of parasitic protozoa and worms

Bacteriology

The scientific study of prokaryotes, including bacteria and archaea

Virology

The scientific study of viruses

Specific Epithet

The second or species name in a scientific binomial

Immunology

The study of a host's defenses to a pathogen

Genomics

The study of genes and their function

Recognize the system of scientific nomenclature that uses two names; a genus and a specific epithet.

The system of nomenclature (naming), for organisms was established in 1735 by Carolus Linnaeus. Scientific names are italicized because Latin was the language traditionally used by scholars. Scientific nomenclature assigns each organism two names -- the genus is the first name and is always capitalized; the specific epithet (species name) follows and is not capitalized. The organism is referred to by both the genus and the specific epithet, and both names are underlined or italicized.

Biogenesis

The theory that living cells arise only from pre-existing cells

Bioremediation

The use of microbes to remove an environmental pollutant

Gene Therapy

Treating a disease by replacing abnormal genes

Chemotherapy

Treatment of disease with chemical substances

Name two beneficial uses of bacteria.

Two beneficial uses of bacteria include the following: 1. Microbial fermentation helps produce many foods & beverages. Latic acid bacteria are used in producing milk, yogurt, pickles, olives, etc. Bacteria are also involved in making fermentated meats, producing vinegar, chocolate, soy sauce, etc. 2. Bacteria can be genetically modified to produce human vaccines like insulin, which is required for diabetic patients.

Protozoa

Unicellular eukaryotic organism; usually chemoheterotrophic

Name two examples of biotechnology that use recombinant DNA technology and two examples that do not.

Using recombinant DNA technology in agriculture, introducing genes that increase available iron levels in Rice three-fold is a potential remedy for Iron deficiency. In medicine, new genetic therapies using rDNA strategies are employed to treat diseases such as cystic fibrosis, AIDS and cancer, wherein, "defective" gene is replaced by the desired "potential" gene. Example of biotechnology that do NOT use recombinant DNA technology: Direct synthesis of enzymes by culturing source organisms, and production of industrially useful products.

Who said living cells arise from pre-existing living cells?

Virchow

Into which field of microbiology would the following scientists best fit? Researcher who studies the causative agent of Ebola hemorrhagic fever a. Biotechnology b. Immunology c. Microbial ecology d. Microbial genetics e. Microbial physiology f. Molecular biology g. Mycology h. Virology

Virology

Which microoorganism is best described by "not composed of cells"?

Viruses

Who used bacteria to produce acetone?

Welzmann

Is it possible to purchase the following microorganisms in a retail store? a. Bacillus thuringiensis b. Saccharomyces If so, provide a reason for buying each.

Yes... B. thuringiensis is sold as a biological insecticide. Saccharomyces is the yeast sold for making bread, wine, and beer.

Which of the following is the most important element of Koch's germ theory of disease? The animal shows disease symptoms when a. the animal has been in contact with a sick animal. b. the animal has a lowered resistance. c. a microorganism is observed in the animal. d. a microorganism is inoculated into the animal. e. microorganisms can be cultured from the animal.

a microorganism is inoculated into the animal.

Which of the following is an example of bioremediation? a. application of oil-degrading bacteria to an oil spill b. application of bacteria to a crop to prevent frost damage c. fixation of gaseous nitrogen into usable nitrogen d. production by bacteria of a human protein such as interferon e. all of the above

application of oil-degrading bacteria to an oil spill

It has been said that bacteria are essential for the existence of life on Earth. Which of the following is the essential function performed by bacteria? a. control insect populations b. directly provide food for humans c. decompose organic material and recycle elements d. cause disease e. produce human hormones such as insulin

decompose organic material and recycle elements

Which of the following is NOT a characteristic of bacteria? a. are prokaryotic b. have peptidoglycan cell walls c. have the same shape d. grow by binary fission e. have the ability to move

have the same shape

Recombinant DNA is a. DNA in bacteria b. the study of how genes work c. the DNA resulting when genes of two different organisms are mixed d. the use of bacteria in the production of foods e. the production of proteins by genes

the DNA resulting when genes of two different organisms are mixed

Who was the first to observe bacteria?

van Leeuwenhoek