question

Aseptic

answer

a procedure designed to kepp unwanted m.o. from without contaminating a pure culture, the sterile medium or surroundings. in lab, ________ technique is accomplished by use of the Bunsen burner flame to sterilize the loop and the mouths of the media tubes.

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Ubiquitous

answer

the microorganisms can be found just about anywhere, especially soil, water, plants, and animals including humans.

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free-living

answer

organisms that do not reside on or in a specific plant for animal host and are not known to cause disease.

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Host

answer

an organism that serves as the home or feeding ground of another organism.

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Nonpathogenic

answer

object or organism that is not known to cause disease.

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pathogen

answer

object or organism that are known to cause disease

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commensal

answer

a relationship between two organisms in which one organism serves as the host to another organism and the host is neither helped nor harmed as a result of the relationship.

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mutualistic

answer

a mutually beneficial relationship between two organisms in which one organism serves as the host to another organism.

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opportunistic pathogen

answer

microorganisms that are normal residents of a host but can cause disease when the host’s defenses are weakened by such factors as poor nutrition or decreased immunity due to sickness. Therefore, it is capable of producing a disease state if introduced into a suitable part of the body.

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mixed culture

answer

a microbial culture consisting of two or more species.

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pure culture

answer

a microbial culture consisting of only a single species.

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isolation technique

answer

is a method of isolating an individual species from a mixed sample that can then be grown as a pure culture or used in the identification of the unknown species.

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Streak plate

answer

is an isolation technique in which a (mixed) bacterial sample is streaked over the surface of a plated agar medium. During streaking the cell density decreases which leads to the isolation of individual cells on the agar surface.

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Colony

answer

a visible cluster of bacteria growing on the surface of or within a solid medium. Additionally, all organisms within the colony descend from a single ancestor and are therefore genetically identical

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Colony forming unit

answer

viable bacteria cells that form colonies which arise from individual cells, pairs, chains, or clusters of cells.

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Round

answer

sphere, circle, without edge

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irregular

answer

uneven, lopsided, asymmetrical

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punctiform

answer

very smally in size, pin-point,

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entire

answer

smooth with no irregularities

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undulate

answer

wavy

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lobate

answer

lobed

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Filamentous

answer

long strand of cells joined end to end, fibrous like spindles of thread

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Rhizoid

answer

branched like roots

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Flat

answer

very smooth or level with medium

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Raised

answer

elevated, projecting upward from a flat medium

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Convex

answer

bowed and has a surface the curves outward

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Pulvinate

answer

very convex or very bowed

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Umbonate

answer

raised in the center

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Moist

answer

Damp, wet

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Mucoid

answer

resembles mucus

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Dry

answer

arid, waterless, desiccated

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Opaque

answer

not clear

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Translucent/Transparent

answer

clear, can see through

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Shiny

answer

glossy, polished

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Dry

answer

Dull, lack of sheen

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Filiform

answer

dense and opaque with a smooth edge

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pigment

answer

color

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Friable

answer

crusty

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Spreading edge

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outgrowth that is scattered or thinning

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Pellicle

answer

membrane that forms on the surface of a liquid medium; a thin layer or film that forms on the surface of the medium as a result of bacterial growth.

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Sediment

answer

residue, deposit, dregs

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Uniform fine turbidity

answer

slight cloudiness that is even throughout the liquid medium

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Flocculent

answer

a clump of growth in a liquid medium

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Autotrophs

answer

require the least assistance from the environment to grow. They are organisms that obtain their food molecules without eating other organisms or substances derived from other organisms

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Heterotrophs

answer

require preformed organic compounds from the environment to grow. They are organisms that obtain organic food molecules by eating other organism or their own by-products

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Fastidious

answer

organisms that rely heavily on the environment to supply ready-made organic compounds.

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Nonfastidious

answer

organism that do not rely on the environment to supply ready-made organic compounds

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Undefined media / complex media

answer

media that are composed of extracts from plant or animal sources and are rich in nutrients. It supports the growth of a greater variety of culturable microbes.

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Defined media

answer

media in which the amount and identity of every ingredient is know. It supports a narrower range of organisms

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Refraction

answer

is the bending of light as it passes through the objective lens.

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Ocular Lens

answer

eyepiece or part of the microscope that the user looks through to see the magnified image of the specimen

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Objective lens

answer

is the optical element that gathers light from the object being observed and focuses the light rays to produce a real image. Objectives can be single lenses or mirrors, or combinations of several optical elements and come in a range of different levels of magnification.

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Resolution

answer

clarity of an image

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Chromagen

answer

a colored molecule, usually a benzene derivative

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Chromophore

answer

portion of the chromagen that gives it its color

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Auxochrome

answer

is the charged portion of the chromagen that allows it to act as a dye through ionic or covalent bonds between the chromagen and the cell.

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Basic Stain

answer

basic refers to alkalinity and as such the stains are attracted to the negative charges on the surface of the cell thereby coloring the cells.

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Heat-fix

answer

is applied to a bacterial smear prior to staining and functions by killing the bacteria, making them adhere to the slide, and coagulating the cytoplasmic proteins to make them more visible. It also distorts the cells to some extent.

question

Wet mount prep.

answer

is made by placing the specimen in a drop of water on a microscope slide and covering it with a cover slip. Because no stain is used, the cells are transparent. Wet mounts are used to observe living cells and determine motility. It may also be used to observe the natural size, arrangement, and shape of the microbial cells.

question

Hanging drop prep.

answer

a thin ring of petroleum jelly is applied around the well of a concave slide then a drop of water is placed on a cover slip and a live bacterial sample is deposited in the water droplet. Lastly, the concave slide is placed over the cover slip in such a way that the drop is received into the depression and is undisturbed. Hanging drops allow for longer observation of the specimen because it doesn’t dry out as fast. It is used to observe living cells and determine motility. It may also be used to observe the natural size, arrangement, and shape of the microbial cells.

question

Brownian motion

answer

motion created by collisions of the bacteria with water molecules causing the organism to move around in a jerky, irregular pattern or appear to vibrate in place.

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Differential stain

answer

stains that detect differences between organisms or differences between parts of the same organism

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Structural Stain

answer

stains that can detect other cellular attributes such as capsules, spores, or flagella.

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Decolorization

answer

alcohol or acetone that is used to remove crystal violet from gram negative cells during a gram stain procedure.

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Primary stain

answer

the first stain applied to a heat-fixed bacterial smear. During a gram stain procedure, the primary stain is crystal violet.

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Mordant

answer

substance used to set or fix a stain/dye. During a gram stain procedure, the mordant is Iodine.

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Counterstain

answer

the second stain applied to a heat-fixed bacterial smear usually following a decolorization step. During a gram stain procedure, the counterstain is safranin.

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Over-decolorize

answer

is caused by leaving the decolorizer (alcohol or acetone) on too long resulting in pinkish-red gram positive cells.

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Under-decolorize

answer

is caused by not leaving the decolorizer (alcohol or acetone) on long enough resulting in purple gram negative cells.

question

Mycolic acid

answer

are long fatty acids found in the cell walls of the bacteria genus Mycobacterium which includes pathogens Mycobacterium tuberculosis and Mycobacterium leprae, the causative agent of the disease tuberculosis and leprosy, respectively. It is a waxy substance that gives acid-fast cells a higher affinity for the primary stain and resistance to decolorization by an acid alcohol solution.

question

Acid-Fast stain

answer

a differential stain used to detect cells capable of retaining a primary stain when treated with an acid alcohol. It is important in the identification of bacteria in the genus Mycobacterium, some of which are pathogenic.

question

Endospore

answer

is a dormant form of a bacterium that allows it survive poor environmental conditions.

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Keratin

answer

is a fibrous structural protein that makes up the outer covering of the spores and is responsible for the spore’s resistance to heat and chemicals.

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Vegetative cell

answer

a cell that is capable of actively growing.

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Spore mother

answer

cells that produce spores or give rise to spores.

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Saphrophyte

answer

an organism that grows on and derives its nourishment from dead or decaying organic matter.

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Central

answer

spores that are located in the middle of the cell.

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Terminal

answer

spores that are located at the end of the cell

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Subterminal

answer

spores that are located between the middle and the end of the cell.

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Spherical

answer

round, circular

question

Elliptical

answer

oval

question

Aerotolerance

answer

the ability or inability of an organism to live in the presence of oxygen.

question

Anaerobic

answer

lacking oxygen, this usually refers to the portion of a liquid or solid medium that is at the bottom.

question

Aerobic

answer

containing oxygen, this usually refers to the portion of a liquid or solid medium that is nearest the top.

question

Obligate (strict) aerobe

answer

organisms that require oxygen for respiration and tend to grow at the top of a liquid or solid medium where the environment is aerobic and oxygen is plentiful.

question

Facultative anaerobe

answer

organisms that grow in the presence or absence of oxygen. When oxygen is available they respire aerobically and when oxygen is unavailable they have the ability to respire anaerobically or ferment an available substrate.

question

Aerotolerant anaerobe

answer

organisms that do not require oxygen and are not negatively affected by it. These organisms live uniformly throughout a liquid or solid medium.

question

Microaerophile

answer

organisms that can only survive in environments that contain lower than atmospheric levels of oxygen.

question

Capnophile

answer

organisms that can only survive if carbon dioxide levels are elevated.

question

Obligate (strict) anaerobe

answer

organisms whose growth is jeopardized by even the smallest amounts of oxygen. Anaerobic bacteria generally grow towards the bottom of liquid or solid media where the environment is anaerobic.

question

Cardinal temperatures

answer

are the minimum, maximum, and optimum growth temperatures for an organism.

question

Psychrophile

answer

organisms that only grow below 20°C. They are commonly found in the snow, refrigerators, the ocean, Arctic, and Antarctic habitats where the temperature remains permanently cold with little or no fluctuation.

question

Psychrotroph

answer

organisms adapted to cold habitats that fluctuate from about 0°C to above 30°C.

question

Mesophile

answer

organisms adapted to temperatures between 15 and 45°C. These organisms may be found in the soil, in the human body, and in animals.

question

Thermophile

answer

organisms adapted to temperatures above 40°C. These organisms may be found in composting organic materials, volcanoes, and in hot springs.

question

Obligate thermophile

answer

thermophiles that will not grow below 40°C.

question

Facultative thermophile

answer

thermophiles that will grow below 40°C.

question

Extreme thermophile

answer

thermophiles that grow best above 80°C. These organisms are generally found in habitats that have a temperature range of 65 to 110°C such as hot ocean floor ridges.

question

pH (“pondus hydrogenii”)

answer

is a measure of the concentration of hydrogen ions in a solution. It ranges in value from 0 to 14.

question

Acidophile

answer

organisms that are adapted to grow well in environments below about pH 5.5.

question

Neutrophile

answer

organisms that prefer levels between 5.5 and 8.5.

question

Alkaliphile

answer

organisms that live above pH 8.5.

question

Denature

answer

for proteins, denaturation is a process in which a protein unravels and loses its native conformation thereby becoming biologically inactive. Denaturation occurs under extreme conditions of pH, salt concentrations (NaCl), and temperature.

question

Turgor pressure

answer

is the force directed against a cell wall after the influx of water and the swelling of a walled cell due to osmosis.

question

Plasmolysis

answer

is a phenomenon caused by placing a cell in a high solute concentration (hypertonic solution) that results in the liquid flowing out of the cell in order to equalize the solute concentrations.

question

Diffusion

answer

the spontaneous tendency of a substance to move down its concentration gradient from a more concentrated to a less concentrated area.

question

Solute

answer

a substance that is dissolved in a solution.

question

Osmosis

answer

is the diffusion of water across a selectively permeable membrane. It is the tendency for water to move in a manner that will equalize the concentration in all parts of a system.

question

Osmotic pressure

answer

is a measure of the tendency of a solution to take up water when separated from pure water by a selectively permeable membrane. It is the force that controls osmosis.

question

Hyposmotic

answer

is a solution with a low osmotic pressure. When a bacterial cell is placed in a hyposmotic environment, there will be a net movement of water INTO the cell. This usually causes the cell to burst.

question

Hyperosmotic

answer

is a solution with a high osmotic pressure. When a bacterial cell is placed in a hyperosmotic environment, there will be a net movement of water OUT of the cell. This usually causes the cell to shrink.

question

Isosmotic

answer

is a solution that has an osmotic pressure that is equal to that of the cell, there is no net movement. Water will move in both directions (into and out of the cell) equally.

question

Halophile

answer

is an organism that grows optimally in NaCl concentrations of 3% or higher.

question

Extreme halophile

answer

is an organism that has specialized cell membranes and enzymes that require salt concentrations of 15% up to about 25% and will not survive where the salinity is lower.

question

Osmotolerant

answer

organisms that will grow over a wide range of salinities. These organisms tolerate or may require high osmotic pressure for survival.

question

Ultraviolet radiation

answer

portion of the electromagnetic spectrum between X-rays and visible light which is between 40 and 400 nm.

question

Electromagnetic energy

answer

a form of energy that is reflected or emitted from objects in the form of electrical and magnetic waves that can travel through space.

question

Serratia marcescens
;
[image]

answer

;
Colonies of this microbe are red in appearance, circular and have an entire margin.
;
[image]

question

oil immersion

answer

100x is used

question

1. smallest
2. fine focus

answer

start at the __________ objective and gradually increase magnification by changing to the next highest objective and using the _____ ______ knob to focus in on the specimen

question

Three common basic stains:

answer

Methylene Blue, Crystal Violet, and Safranin.

question

color of a gram +

answer

purple

question

color of a gram -

answer

pinkish

question

Negative Staining Tech.

answer

This is a staining technique that used a dye solution in which the chromagen is acidic and carries a negative charge. The negative charge on the bacterial surface repels the negatively charged chromagen so that the cell remains unstained against a colored background.

question

Reason to used neg. stain tech.

answer

The _________ ___________ technique is used to determine morphology and cellular arrangement in bacteria that are too delicate to withstand heat-fixing.

question

Gram Negative

answer

______ _______ cells do not retain crystal violet because the decolorizer extracts the lipid causing the this type of cell's cell wall to be more porous and incapable of retaining crystal violet

question

Gram +

answer

_________ __________ retain crystal violet because they have a thicker peptidoglycan layer and a greater degree of cross-linking due to teichoic acids which allows the cell to retain the crystal violet stain

question

Acid Fast Stain

answer

This is a differential stain used to detect cells capable of retaining a primary stain when treated with an acid alcohol. It is used to identify bacteria in the genus Mycobacterium some of which are pathogenic.

question

Spore Stain

answer

Malachite green is the primary stain and Safranin is the counterstain when performing a ______ ______.

It is a differential stain that is used to detect the presence and location of spores in bacterial cells.

question

Bacillus and Clostridium.

answer

The two genera of bacteria produce spores are ________ & ________.

question

Deep stab

answer

When inoculating an agar _________ ________ you use an inoculating needle by inserting the needle straight down the center of the medium without touching the bottom of the tube then pull the need straight back out without wiggling to avoid creating a large hole in which air may enter the media altering the aerobic capacity of the media.

question

fluid thioglycollate media

answer

this is designed to promote the growth of a wide variety of fastidious microbes. It is also used represent the various levels of oxygen tolerance of the microbes being cultivated.

question

aerobic zone

answer

this area is the only portion of the media that is accessible to oxygen due to the deepness of the medium.

Lab ex. include: Bacillus cereus and Pseudomonas aeruginosa.

question

Anaerobic Jar

answer

This is used To create an anaerobic environment in order to compare the growth of bacteria with various levels of aerotolerance.

Reaction to know. 2H2 + 02 = 2H20
**water is product.

question

Bacillus stearothermophilus

answer

only m.o used in lab to show groth at 55°C.

question

UV

answer

___ light inhibits growth of bacteria

question

Colony Morphology

answer

[image]

question

Bacillus Subtilis
B.sub

answer

Colonies are larger, but not as large as B. cereus. The margin is undulate, with circular form and flat elevation. [image]

question

Bacillus Cereus
;
B. cereus
;
[image]

answer

Colonies are large, irregular and flat with an undulate margin [image]

question

B. cereus

answer

Name this Gram + rod
;
[image]

question

B. sub

answer

Tube culture of what m.o.?
;
[image]

question

Escherichia coli
E.coli
;
[image]

answer

This microbe forms medium sized, moist, light yellow/white colonies with an entire/smooth margin and umbonate elevation.
;
[image]

question

E. coli

answer

Name this Gram - rod.
;
[image]

question

Innoculation Technique

answer

What is this?
;
[image]

question

;
Klebsiella pneumoniae
;
[image]

answer

This microbe forms white, opaque colonies that are circular with a convex elevation and an entire/smooth margin.
;
[image]

question

Anaerobic: left
;
Aerobic: right

answer

Which side is anaerobic? aerobic?
;
[image]

question

Loop and Needle

answer

[image]

question

Negative Stain

answer

What type of stain is this?
;
[image]

question

;
Staphylococcus aureus
Klebsiella pneumoniae
Escherichia coli
Showed no unique growth.

answer

This is no unique growth. What m.o's did we use that had this?
;
[image]

question

Obligate aerobe

answer

;
Bacteria that cannot grow in the absence of oxygen will not grow very deeply into the medium, which becomes anaerobic a short distance below the surface.
;
[image]

question

More patterns in culture broth
[image]

answer

The patterns of culture in broth
[image]

question

Serratia marcescens

answer

What m.o. is this?
;
[image]

question

Spore Stain

answer

What type of stain is this?
;
[image]

question

Spread Plate Technique

answer

What technique is this?
;
[image]

question

;
Staphylococcus aureus
;
[image]

answer

;
This microbe forms large, round, convex, golden colonies that appear shiny
;
[image]

question

;
Staphylococcus aureus

answer

What gram + cocci is this?
;
[image]

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