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Microbiology Exam1study guide
Microbiology Exam1study guide
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Microbiology
Undergraduate 1
03/16/2010

Additional Microbiology Flashcards

 


 

Cards

Term
Microbiology
Definition
Study of organisms too small to be clearly seen by the unaided eye (microorganisms) Prominent Figures in Microbiology
Term
Anthony van Leeuwenhoek (1632-1723)
Definition

 

  • First person to observe and describe microorganisms accurately
  • Conflict over Spontaneous Generation
  • Living organisms can develop from nonliving or decomposing matter

 

Term
Francesco Redi (1626-1697)
Definition

 

  • Disproved spontaneous generation for large animals
  • Showed that maggots on decaying meat came from fly eggs

 

Term
John Needham (1713-1781)
Definition

 

  • His experiment
  • Mutton broth in flasks→ boiled → sealed
  • Results: became cloudy and contained microorganisms

 

Term
Lazzaro Spallanzani (1729-1799)
Definition

 

  • His experiment
  • Broth in flasks → sealed → boiled
  • Results: no growth of microorganisms

 

Term
John Tyndall (1820-1893)
Definition

 

  • Demonstrated that dust carries microorganisms
  • Showed that if dust was absent, nutrient broths remained sterile, even if directly exposed to air
  • Also provided evidence for the existence of exceptionally heat-resistant forms of bacteria

 

Term
Agostini Bassi (1773-1856)
Definition

Showed that a disease of silkworms was caused by a fungus

Term
M.J. Berkeley (ca. 1845)
Definition

Demonstrated that the great Potato Blight of Ireland was caused by a water mold

Term
Henrich de Bary (1853)
Definition
Showed that smut and rust fungi caused cereal crop diseases
Term
Joseph Lister (1827-1912)
Definition

 

  • Provided indirect evidence that microorganisms were the causal agents of disease
  • Developed a system of surgery designed to prevent microorganisms from entering wounds as well as methods for treating instruments and surgical dressings
  • His patients had fewer postoperative infections

 

Term
Charles Chamberland (1851-1908)
Definition

 

  • Developed porcelain bacterial filters used by Ivanoski an Beijerinck to study tobacco mosaic disease
  • Determined that extracts from diseased plants had infectious agents present which were smaller than bacteria and passed through the filters
  • Infectious agents were eventually shown to be viruses

 

Term
Edward Jenner (ca. 1798)
Definition

 

  • Used a vaccination procedure to protect individuals from smallpox
  • This preceded the work establishing the role of microorganisms in disease

 

Term

Emil von Behring (1854-1917)

Shibasaburo Kitasato (1852-1931)

Definition

 

  • Developed antitoxins for diphtheria and tetanus
  • Evidence for humoral immunity

 

Term
Elie Metchnikoff (1845-1916)
Definition

 

  • Discovered bacteria-engulfing, phagocytic cells in the blood
  • Evidence for cellular immunity

 

Term

Sergei Winogradsky (1856-1953)

Marinus Beijerinck (1851-1931)

Definition

 

  • Studied soil microorganisms and discovered numerous interesting metabolic processes (eg., nitrogen fixation)
  • Pioneered the use of enrichment cultures and selective media

 

Term
Alexander Fleming (1929)
Definition

 

  • Discovered that the fungus Penicillium produced what he called penicillin
  • The first antibiotic that could successfully control bacterial infections

 

Term
Louis Pasteur (1822-1895)
Definition
  • His experiments:                                                                                             • Placed nutrient solution in flasks                                                 • Created flasks with long, curved necks                                       • Boiled the solutions                                                                       • Left flasks exposed to air                                                             • Results: no growth of microorganisms
  • Final blow to theory of spontaneous generation
  • Showed that the pebrine disease of silkworms was caused by a protozoan

 

Term
Pasteur and Roux
Definition
Discovered that incubation of cultures for long intervals between transfers caused pathogens to lose their ability to cause disease
Term
Pasteur and his coworkers
Definition

 

  • Developed vaccines for chicken cholera, anthrax, and rabies
  • Demonstrated that alcohol fermentations and other fermentations were the result of microbial activity

 

Term
Robert Koch (1843-1910)
Definition

 

  • Established the relationship between Bacillus anthracis and anthrax
  • Used criteria developed by his teacher Jacob Henle (1809-1895)
  • These criteria now known as Koch’s postulates
  • Still used today to establish the link between a particular microorganism and a particular disease

 

Term
Koch’s Postulates
Definition

 

  • The microorganism must be present in every case of the disease but absent from healthy individuals
  • The suspected microorganism must be isolated and grown in a pure culture
  • The same disease must result when the isolated microorganism is inoculated into a healthy host
  • The same microorganism must be isolated again from the diseased host

 

Term
Koch’s work led to discovery or development of:
Definition

 

  • Agar
  • Petri dish
  • Nutrient broth and nutrient agar
  • Methods for isolating microorganisms

 

Term
Prokaryotic cells
Definition

 

  • Lack true membrane
  • delimited nucleus

 

Term
Eukaryotic cells
Definition

 

  • Have a membrane-enclosed nucleus
  • More complex morphologically and are usually larger than prokaryotic cells

 

Term
1st living organisms on Earth were microorganisms
Definition

 

  • The Universal Ancestor
  • Single-celled rod shaped anaerobic prokaryote

 

Term
Photosynthesis thought to have evolved early in Earth’s history
Definition
Fossil evidence places evolution of cyanobacteria and oxygenic photosynthesis to ≈ 3 billion years ago
Term
Three Domains of Life
Definition

 

  • Archaea
  • Bacteria
  • Eucarya

 

Term
The Universal Phylogenetic Tree
Definition
The root of the tree suggests that the three domains have a single common ancestor, but Archaea and Eucarya evolved independently of Bacteria.
Term
Prokaryotic Evolution
Definition

 

  • Results in microbial diversity which upon selection determines the development of new species
  • Genetic heritable genetic changes in Archaea and Bacteria are introduced by
  1. Mutation
  2. Lateral gene transfer
  3. Prokaryotic Classification and Taxonomy

 

Term
Taxonomy (Three Parts)
Definition

 

  • Classification: arrangement of organisms into groups (taxa; s., taxon)
  • Nomenclature: assignment of names to taxa
  • Identification- determination of taxon to which an isolate belongs

 

Term
Natural Classification
Definition

 

  • Arranges organisms into groups whose members share many characteristics
  • 1st classification in 18th Century developed by Linnaeus
  • Based on anatomical characteristics
  • Doesn’t necessarily provide information on evolutionary relatedness

 

Term
Phenetic Classification
Definition

 

  • Group together based on mutual similarity of phenotypes
  • Can reveal evolutionary relationships, but not dependent on phylogenetic analysis
  • Doesn’t weigh characters
  • Best systems compare as many attributes as possible

 

Term
Phylogenetic Classification
Definition

 

  • Also called phyletic classification systems
  • Phylogeny
  • Evolutionary development of a species
  • Usually based on direct comparison of genetic material and gene products (This approach more feasible because when Woese and Fox proposed using rRNA nucleotide sequences to assess evolutionary relatedness of organisms)

 

Term
Binomial System of Nomenclature
Definition

 

  • Devised by Carl von Linne’ (Carolus Linnaeus)
  • Each organism has two names
  1. Genus name- italicized and capitalized or underlined (eg., Escherichia)
  2. Species epithet-italicized but not capitalized, yet underlined (eg., coli)
  3. Can be abbreviated after first use (eg., E. coli)

 

Term
Techniques for Determining Microbial Taxonomy and Phylogeny (Table 19.5)
Definition

 

  • Classical Characteristics
  • Molecular Characteristics

 

Term
Six Supergroups
Definition

 

  • Opisthokonta
  • Archaeplastids
  • Amoebozoa
  • Rhizaria
  • Chromalveolata
  • Excavata

 

Term
The Five-Kingdom System
Definition

 

  • No longer accepted
  • Scientists prefer to see evolutionary relationships
  • Major problem is lack of distinction between archaea and bacteria
  • Kingdom Protista is too diverse to be taxonomically useful
  • Boundaries between kingdoms Protista, Plantae and Fungi are ill-defined

 

Term
Bergey’s Manual of Systematic Bacteriology
Definition
How we classify bacteria
Term
Giardia
Definition

 

  • Causes diarrhea, common among children, pets
  • Found in untreated water
  • Cysts are very resistant
  • Can resist effects of chlorine
  • Greatest protection is process of filtration (in water)

 

Term
Giardiasis
Definition

 

  • Caused by Giardia intestinalis
  • Forms cysts and trophozoites
  • Transmission usually by cyst-contaminated water
  • Asymptomatic human carriers are common
  • 30,000 cases reported yearly

 

Term
Life Cycle of Giardia (simple)
Definition

 

  • Exposure to quadnucleated cyst (fecal/oral/route)
  • Excystment in small intestine
  • Plasmotomy- quad to 2 binucleated trophs
  • 2 Trophozoites in intestines (active feeding stage)—adhere to cells
  • Binary fission
  • Encystment in large intestine into quadnucleated cyst
  • Cyst exits in feces
  • Giardiasis…

 

Term
Clinical Manifestations
Definition

 

  • Acute giardiasis- severe diarrhea, epigastric pain, cramps, voluminous flatulence and anorexia
  • Chronic gastritis- intermittent diarrhea with periodic appearance of remission of symptoms

 

Term
Parabasilla - Trichonymphida
Definition

 

  • Obligate mutuals of wood-eating insects such as termites
  • Digests cellulose in their gut

 

Term
Parabasilla - Trichomonadida
Definition

 

  • Symbionts of digestive, reproductive and respiratory traits of many vertebrates, including humans
  • Some strains are human pathogens
  • Trichomoniasis: Most common STD—7.4 million new cases every year in the U.S.

 

Term
Euglenozoa
Definition

 

  • Commonly found in fresh water
  • 1/3 are photoautotrophic, rest are chemoorganotrophs/heterotrophic
  • Has characteristics of algae and protozoans
  • Euglena is the representative genus:
  • Cell bounded by plasmalemma (cell membrane)

 

Term
Trypanosomes
Definition
Parasites of plants and animals – big game animals in Africa are carriers
Term
Leishmaniasis
Definition

 

  • Caused by members of genus Leishmania
  • Includes systemic and skin/membrane damage
  • Occasional cases in U.S.—common in the rest of the world: 1.5 million cases each year
  • Flagellated protists
  • Visceral Leishmaniasis—500,000 cases/year

 

Term
Trypanosoma Cruzi
Definition

 

  • Causes S. American Sleeping Sickness (Chagas disease)
  • 10,000,000 people have it
  • Transmitted by “kissing bugs”: bite around the lips and defacate
  • Causes damage to nervous system

 

Term
T. gamiense and T. rhodesiense
Definition
Cause of African Sleeping Sickness
Term
Trypanosomiasis
Definition

 

  • Caused by trypanosomes
  • Group of flagellated protists
  • Transmitted by tsetse flies—(African trypanosomiasis) or kissing bug (Chagas’ disease)
  • Reservoirs include domestic cattle and other animals
  • Motile parasites in blood

 

Term
African Trypanosomiasis
Definition
Interstitial inflammation and necrosis with in lymph nodes and small blood vessels of brain and heart, leading to lethargy and death within 1-3 years
Term
American Trypanosomiasis (Chagas)
Definition
Heart disease and other disorders due to destruction of parasitized cells in the liver, spleen, lymph nodes, and the central nervous system
Term
Amoeba Proteus
Definition

 

  • Commonly used in student labs
  • Present in this phylum

 

Term
Entamoeba Histolytica
Definition

 

  • Causes amoebic dysentery
  • Major parasitic disease
  • More serious than Giardia
  • More invasive organism
  • Not as common in the U.S.

 

Term
Entamoeba Histolytica Life Cycle: (Simple)
Definition

 

  • Exposure to quadnucleated cyst (fecal/oral/route)
  • Excystment in small intestine
  • Schizogony- quad into four single nucleated trophozoites
  • 4 Trophozoites—intestine to other areas—invasive
  • Binary fission
  • Encyst in large intestine into quadnucleated cyst

 

Term
Amebic Meningoencephalitis
Definition

 

  • Caused by the free-living Amoebae Naegleria and Acanthamoeba
  • Caused by jumping in water
  • Enters through sinuses into brain
  • Found in swimming holes
  • 10 cases/year, causes death

 

Term
Radiolaria
Definition

 

  • Most have internal skeleton made of siliceous material : “pretty” structures—when organisms die off, structures remain
  • Sexual and asexual reproduction used

 

Term
Foraminifera
Definition

 

  • Also forms pretty structures
  • Called forams
  • Filopodia are arranged in branching network (reticulopodia)
  • Have characteristics tests arranged in multiple chambers that are sequentially added as organism grows
  • Foram tests make up most modern-day chalk, limestone and marble

 

Term
Dinoflagellata (dinoflagellates)
Definition

 

  • Red tides (have been classified as algae)
  • Large group found in marine plankton
  • Cause phosphorescence and toxic blooms • Eg., Paralytic Shellfish Poisoning—caused by gonyaulax

 

Term
Ciliophora
Definition
Paramecium (ciliated)
Term
Plasmodium
Definition

 

  • Cause of Malaria - Caused by a bite of an infected mosquito—Anopheles mosquito (biological vector)
  • Biological Vector- life cycle occurs in vector itself
  • Mechanical Vector- moves organism from one place to another (eg., housefly, cockroach)

 

Term
Malaria Life Cycle
Definition

 

  • Sporozoites transferred from the salivary gland of the Anopheles mosquito
  • Sporozoites removed from blood by liver and spleen
  • Undergo schizogony into merozoites
  • Some merozoites stay in liver, some merozoites enter circulatory system and invade erythrocytes

 

Term
Erythrocytic Cycle
Definition

 

  • Merozoites transform into trophozoites
  • Trophozoites feed on hemoglobin and then undergo nuclear division into 16-32 nuclei—now called “Schizont”
  • Schizogony—merozoites burst from erythrocytes into circulatory system
  • Merozoites invade more erythrocytes, etc.
  • Cyclical—every 40-72 hours depending on species producing the characteristic fever and chills
  • Some merozoites differentiate into micro and macro gametocytes which stay in the erythrocyte
  • When bitten by a mosquito, the gametocytes are transferred

 

Term
Sexual Cycle
Definition

 

  • Micro and macro gametocytes form into gametes in gut of mosquito
  • Micro and macro gametes undergo syngamy
  • Ookinete (zygote) develops into oocyst
  • Oocyst undergoes nuclear division
  • Oocyst ruptures to release sporozoites
  • Sporozoites penetrate salivary gland
  • The mosquito is now infective

 

Term
Toxoplasma
Definition

 

  • Cause of toxoplasmosis
  • Cat litter—cyst in cat feces
  • Pregnant women—causes very severe birth defects
  • Very diverse parasite

 

Term
Cryptosporidiosis
Definition
  • Caused by Cryptosporidium parvum                               • Apicomplexan that forms cysts, sporozoites and merozoites
  • Fecal/oral/route
  • Controlled in our water supply through filtration
  • Can be fatal in immunocompromised individuals

 

Term

A Chromalveolata Subgroup

Diatoms—Protists (autotrophs)

Definition

 

  • Same shells formed as Radiolaria and Foraminifera (heterotrophs)
  • Found in marine plankton
  • Produce 40%-50% of organic carbon in ocean

 

Term
Volvox
Definition

 

  • Colonial organism
  • Many unicellular organisms functioning together like multicellular

 

Term
Fungi
Definition

 

  • Chemoheterotrophic, not photosynthetic
  • Found wherever moisture, the appropriate temperature and suitable organic nutrients are present
  • Exist as filamentous hyphae • Mycelium- mass of hyphae
  • Secrete exoenzymes to digest insoluble matter, then absorb the solubilized nutrients
  • Have two reproductive structures                                                          • Sporangia from asexual spores                                                  • Gametangia from sexual spores (gametes)
  • A (+) and a (-) strain form a sexual spore
  • Appear genetically identical but together form spores (Rhizopus)

 

Term
Mycotoxicology
Definition
Study of fungal toxins (micotoxins) and their effects
Term
Mycoses
Definition
Disease caused by fungi
Term
Mycoses Distribution
Definition

 

  • Primarily terrestrial—found in moist soil
  • Many are pathogenic in plants or animals

 

Term
Mycoses Structure (Thallus)
Definition

 

  • Undifferentiated structure
  • Body or vegetative structure of a fungus (more animal like)
  • Cell walls usually composed of chitin- store food as glycogen

 

Term
Yeasts
Definition

 

  • Unicellular fungi
  • Reproduce asexually, often by budding
  • Reproduce sexually by formation of spores

 

Term
Molds
Definition

  • Filamentous (hyphae)
  • May be septate or nonseptate

Term
Dimorphism
Definition

 

  • Some change from a yeast to a mold
  • YM shift—caused by temperature                                                              • Outside or room temperature—mold                                              • Body temperature—yeast

 

Term
Mycoses Nutrition and Metabolism
Definition

 

  • Most are saprophytes                                                                                  • Obtain nutrients from dead organic material
  • Secrete hydrolytic enzymes
  • Chemoorganoheterotrophs
  • Glycogen in primary storage polysaccharide
  • Most are aerobic

 

Term
Photoautotrophic
Definition

 

  • Gets its carbon from photosynthesis—organic or inorganic
  • Gets its energy from light and carbon dioxide

 

Term
Chemoorganotrophic/Chemoheterotrophic
Definition
Gets carbon from organic sources and breaks it down for energy
Term
Mixotrophic
Definition
Can use both organic and inorganic forms of carbon
Term
Protozoa
Definition
Traditionally referred to chemoorganotrophic protists
Term
Algae
Definition

 

 

  • Some are multicellular (kelp, seaweed)                                                              Photosynthetic protists                                                        Originally referred to all simple aquatic plants

 

 

Term
Asexual
Definition

 

  • Transverse fission
  • Budding
  • Spore production                                                                                         Conidia- different types, extended from hyphae                           Sporangiospores—enclosed in a sac

 

Term
Sexual
Definition
Involves union of compatible nuclei followed by formation of sexual spores (zygospores, ascopspores, or basidiospores)
Term
Zygomycetes
Definition

 

  • Nonseptate hyphae
  • Asexual sporangia

 

Term
Ascomycetes
Definition

 

  • Septate hyphae
  • Asexual conidiospores

 

Term
Basidiomycetes
Definition

 

  • Septate
  • No asexual spores
  • Ex. Cryptococcus neoformans—cryptococcosis                  • Systemic infection, primarily of lungs and central nervous system

 

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