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143 Cards in this Set
- Front
- Back
what are microbes
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very small organisms that usually require a microscope to be seen/not seen with unaided eyes
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what are microbes also called
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microorganisms
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what does the microbe group include
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bacteria, fungi, protozoa, and microscopic algae, viruses
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the majority of microorganisms make crucial contributions to the welfare of the world's inhabitants by
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helping to maintain the balance of living organisms and chemicals in our environment
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certain microbes play important roles in
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photosynthesis
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what is photosynthesis
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a food and oxygen generating process that is critical to life on Earth
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humans and many other animals depend onthe microbes in their ______ for digestion and the _________ of some vitamins that their body requires
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intestines, synthesis
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B vitamins are for
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metabolism
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vitamin K is for
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blood clotting
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microorganisms also have many commercial _______
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applications
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who discovered the process by which microbes produce acetone and butanol in 1914
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Chaim Weizmann
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what is Weizmanns history
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Russian born chemist working in England
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How did Weizmann's discovery play a significant role in determining the outcome of world war I
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acetone was very important for making cordite-a smokeless form of gunpowder used in munitions
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microbes are used in the synthesis of chemical products such as
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aceton, organic acids, enzymes, alcohols, and many drugs
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the food industry uses microbes in producing
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vinegar, sauerkraut, pickles, alcoholic beverages, green olives, soy sauce, buttermilk, cheese, yogurt, and bread
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enzymes from micrboes can now be manipulated such that the microbes produce substances they normally ________
what are examples of these substances |
do not synthesize
cellulose, digestive acids, drain cleaner, iportant therapeutic substances such as insulin |
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Though only a minority of microorganisms are ________, practical knowledge of microbes is necessary for medicine and the related health sciences.
example? |
pathogenic
hospital workers must be able to protect patients from common microbes that are normally harmless but pose a threat to the sick and injured |
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what does pathogenic mean
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disease producing
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why did so many people die long ago
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devastating epidemics,
vaccinations and antibiotics were not available |
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who established the system of nomenclature for organisms in 1735
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Carolus Linnaeus
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why are scientific names latinized
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because Latin was the language traditionally used by scholars
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what is the genus
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the first name and is always capitalized
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what is the specific epithet
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the species name and is not capitalized
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the organism is referred to by both the genus and the specific epithet and both names are
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underlined and italicized
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after a scientific name has been mentioned once, it can be abbreviated by
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abbreviate the inital of the genus followed by the specific epithet
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what can scientific names do
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describe an organism
honor a researcher identify the habitat of a species |
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where is staphylococcus aureus commonly found
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on human skin
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what does staphylo mean
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clustered arrangement of the cells
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waht does coccus indicate
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they are shaped like spheres
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what does the specific epithet, aureus, mean
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Latin for golden, the color of many colonies of this bacterium
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what is the genus of the bacterium escherichia coli
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for a scientist, Theodor Escherih
E.Coli |
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how did sourdough bread get it's name
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during the gold rush, miners baked so many sour loaves that they were nicknamed sourdough
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what kingdom does yeast belong to
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fungi
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what is the process of when the yeast metabolizes the sugars and produces alcohol (ethanol) and carbon dioxide as waste products
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fermentation
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the most famous sourdough bread comes from
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San Francisco
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sourdough bread is ___ times more acidic than conventional bread because of the ...
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8-10
presence of lactic and acetic acids |
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what is bacteria
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relatively simple, single-celled(unicellular) organisms
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why are bacterial cells called prokaryotes
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because their enetic material is not enclosed in a special nuclear membrane
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prokaryotes include both the _____ and the _____
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bacteria & archaea
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what are the most common shapes that bacterial cells appear in
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bacilus(rodlike)
coccus(spherical/oval) spiral(corkscrew/curved) |
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some bacteria are __________ shaped
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star or square
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individual bacteria may form
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pairs, chains, clusters or other groupings
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bacteria are enclosed in cell walls tat are
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largely composed of peptidoglycan
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what is pptidoglycan
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a carbohydtrate and protein complex
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how do bacteria generally reproduce
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binary fission
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wat is binary fission
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dividing into two equal cells
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what do most bacteria use for nutrition
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organic chemicals, can be derived from either dead or livig organisms in naure
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many macteria can "swim" by using moing appendages called
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flagella
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archaea consists of prokaryotic cells, but if they have cell walls then
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the walls lack pepdioglycan
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where are archaea often found in
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extreme environments
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what are the three groups that archaea is divided into
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methanogens
extreme halophiles extreme thermophiles |
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what are methanogens
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produce methane as a waste product from respiration
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what are extreme halophiles
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(salt loving)
live in extremely salty environments such as the Great Salt Lake and the Dead Sea |
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what are extreme thermophiles
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(heat)
live in hot sulfurous water such as hot springs at Yellowstone National Park |
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archaea are not known to cause ______ in humans
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disease
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are fungi prokaryotes or eukaryotes
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eukaryotes
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what is fungi
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organisms whose cells have a distinct nucleus containing the cell's genetic material (DNA), surrounded by a special envoleope called the nuclear membrane
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organisms in the Kingdom Fungi can be unicellular or
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multicellular
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why aren't large multicellular fungi that look like plants, plants?
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they cannot carry out photosynthesis like most plants
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true fungi have cell walls composed primarily of a substance called
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chitin
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what are yeasts
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the unicellular forms of fungi
oval microorganisms that are larger than bacteria |
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what is the most typical fungi
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molds
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molds form visible masses called
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mycelia
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what is mycelia composed of
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long filaments that branch and intertwine
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what are long filaments
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hyphae
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fungi can reproduce
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asexually or sexually
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fungi obtain nourishment by
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absorbing solutions of organic material from their environment-whether soil, seawater, fresh water, or an animal or plant host
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what are slime molds
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have characteristics of both fungi and amoebas
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protozoa are unicellular or multicellular
prokaryotic or eukaryotic microbes |
unicellular
eukaryotic microbes |
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how do protozoa move
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by pseudopods, flagella or cilia
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how do amoebas move
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by using extensions of their cytoplasm called pseudopods
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what are pseudopods
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false feet
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what are cilia
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numerous shorter appendages for locomotion
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protozoa have a variety of shapes and live either as free
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entities or as parasitesthat absorb or ingest organic compounds from their environment
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what are parasites
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organisms that derive nutrients from living hosts
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protozoa can reproduce
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sexually or asexually
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what are algae
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photosynthetic eukaryotes with a wide variety of shapes and both sexual and asexual reproductive forms
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the algae of interest to microbiologists are usually
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unicellular
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what are the cell walls of many algae composed of
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a carbohydrate called cellulose
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algae are ____ in fresh and salt water, in soil, and in association with plants
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abundant
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what do algae need for food production and growth
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light, water, and carbon dioxide
don't generally require organic compounds from the environment |
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what does algae produce as a result of photosynthesis
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oxygen and carbohydrates that are then utilized by other organisms
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most viruses can be seen only with
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an electron microscope
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viruses are unicelular?
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no, acellular
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what does acellular mean
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not cellular
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what does a virus particle contain
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a core made ofonly one type of nucleic acid, ether DNA or RNA
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what is the core of a virus surrounded by
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a protein coat
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sometimes the coat of a virus is encased by an additional layer
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a lipid membrane called the envelope
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viruses can reproduce only by
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using the cellular machinery of oter organisms
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viruses are considered to be living
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when they multipoly within host cells they infect, so viruses are parasites of other forms of life
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viruses are not considered to be living because
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outside of living hosts they are inert
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what are the two groups of parasitic worms
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flatworms
roundworms |
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what are roundworms collectively called
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helminths
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before the existence of microbes was known, all organisms were grouped into either the _______ or _________ kingdom
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animal or plant
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what are the three domains of Carl Woese's system of classification
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1. Bacteria (cell wals contain a protein carbohydtrate complex called peptidoglycan)
2. Archaea (cell walls, if present, lack peptidolycan) 3. Eukarya: -Protists (slime molds, protozoa, and algae) -Fungi(unicellular yeasts, multicellular molds, and mushrooms) -Plants(includes mosses, ferns, conifers, and flowering plants) -Animals(sponges, worms, insects, and vertebrates) |
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what is the cell theory
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the theory that all living things are composed of cells
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what did Hooke lack even though his icrocope was capable of showing cells
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staining techniques
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who was the first to observe live microorganisms through the magnifying lenses of morethan 400 microcopes he constructed
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Anton van Leeuwenhoek
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spontaneous generation
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many scientists and philosophers beleived that some forms of life could arise spontaneously from nonliving matter
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What did John Needham find
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even after he heated nutrient fluids before pouring them into covered flasks, the cooled solutions were soon teeming with microorganisms
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what did needham claim
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that microbes developed spontaneously from the fluids
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what did Lazzaro Spallanzani suggest 20 years later
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microorganisms from the air proably had entered Needham's solutions after they were boiled
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what did Spallanzani show
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that nutrient fluids heated after being sealed in a flask did not develop microbial growth
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how did Needham claim by responding to Spallanzani
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by claiming the "vital force" necessary for spontaneous generation had been destroyed by te heat and was kept out of the flasks by the seals
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when was the intangibe "vital force" given all the more credence after Spallanzani's experiment
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when Anton Laurent Lavoisier showed the importance of oxygen to life
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Spallanzani's observations were crticized on the grounds that there was not enough oxygen in the sealed flasks to support
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microbial life
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who challenged the concept of biogenesis
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Rudolf Virchow
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what is biogenesis
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the claim that living cells can arise only frm preexisting living cells
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who resolved the issue on spontaneous generation
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Louis Pasteur, french scientist
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what did Pasteur demonstrate
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that microorganisms are present in the air and can contaminate sterile solutions
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what did pasteur do to prove his point
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-filled several short-necked flasks with beef broth and then boiled their contents
-some were left open and allowed to cool -in a few days, the flasks were found to be contaminated with microbes |
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what did Pasteur reason from his results
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that microbes in the air were the agents responsible for conaminating nonliving matter such as the broths in Needham's flasks
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what did Pasteur do next
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-he placed broth in open-ended long-necked flasks and ent the necks into S-shaped curves
-contents of the flask were boiled and cooled -broth did not decy and showed no signs of life even after months |
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Pasteur's unique design allowed air to pass into the flask, but the curved neck
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trapped any airborne microorganisms that might conaminate the broth
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Pasteur showed that microorganisms can be present in nonloving matters on -
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on solids, in liquids, and in the air
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what did pasteur furthermore demonstrate
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that microbial life can be destroyed by heat and that methods can be devised to block the access of airborne microorganisms to nutrient environments
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what are aseptic techniques
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techniques that prevent contamination by unwanted microorganisms, which are now the standard practice in laboratory and many medical procedures
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what are among the first and most important changes that a begining microbiologist learns
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modern aseptic techniques
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scientists now beleive that a form of spontaneous gerenation probably did occur on the primitive Earth when life first began, but
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they agree that this does not happen under today's environmental conditions
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what were the years of 1857-1914 known as
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the Golden Age of Microbiology
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what happened during this period
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the rapid advances mainly by Pasteur and Koch led to the establishment of microbiology as a science
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what discoveries were made in the Golden Age of Microbiology
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agents of many diseases and the role of immunity in the prevention and cure of disease
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what did microbiologists study during this period
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chemical activities of microorganisms, improved the techniques for performing microscopy and culturing microorganisms, and developed vaccines and surgical techniques
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when did one of the key steps that established the relationship between microorganisms and disease occur
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when a group of French merchants asked Pasteur to find out why wine and beer soured
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what did the french merchants that asked pasteur to find out why beer and wine soured hope to develop
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a method that would prevent spoilage when those verages were shipped long distances
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what is fermentation
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microorganisms called yeasts convert the sugars to alcohol in the absence of air
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what is used to make wine and beer
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fermentation
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who found the idea of fermentation
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pasteur
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souring and spoilage are caused by different microorganisms called
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bacteria
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in the presence of air, bacteria change the ______ in the beverage into _____
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alcohol
vinegar (acetic acid) |
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what is pasteurization
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to heat the beer and wine just enough to kill most of the bacteria that caused the spoilage
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what is pasteurization commonly used for now
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to reduce spoilage and kill potentially harmful bacteria in milk as well as in some alcoholic drinks
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showing the connection between ______ of food and _________ was a major step twoard establishing the relationship between disease and microbes.
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spoilage
microorganisms |
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what was the first link between the activity of a microorganism and physical and chemical changes in organic materials
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the realizaion that yeasts play a crucial role in fermentation
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germ theory of disease
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microorganisms might have similar relationships with plants and animals - specifically that microorganisms might cause disease
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why was the germ theory a difficult concept for many people to accept at that time
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because for centuries disease was believed to be punishment for an individual's crimes or misdeeds
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whose data did Pasteur use to find more recent infection caused by protozoan and to develop a method for recognizing affected silkworm moths
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Agostino Bassi
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who applied the germ theory to medical procedures
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Joseph Lister
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what did Lister treat surgical wounds with
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a phenol solution
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what did Lister's findings rove
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that microorganisms cause surgical wound infections
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where did the the first proof that bacteria actually causes disease come from
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Robert Koch
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what did Koch discover
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rod-shaped bacteria, known as Bacillus anthracis in the blood of cattle that died of anthrax
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what are koch's postulates
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a sequence of experimental steps for directly relating a specific microbe to a specific disease
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