Microbiology Midterm

Front 1

define innoculation

Back 1

introduction of a small sample of cells into a container with nutrient medium

Front 2

clinical sample

Back 2

blood, urine, CSF, feces, etc.

Front 3

habitat sample

Back 3

soil, water, sewage, food, etc.

Front 4

define what media does

Back 4

supplies nutritional requirements for organisms

Front 5

define simple media

Back 5

few organic compounds

Front 6

define complex media

Back 6

inorganic and organic compounds

Front 7

define liquid media

Back 7

water based solutions, do not solidify at temps above freezing, flow freely in containers i.e. broths, milks, infusions: various solutes dissolved in distilled water.

Front 8

define semi solid media

Back 8

clot like consistency, contain solidifying agent (agar/gelatin) used to determine motility, localized reaction at specific sites

Front 9

solid media

Back 9

firm surface, allows cells to form discrete colonies: advantageous for ISOLATION/SUBCULTURING

Front 10

what are the two types of solid media?

Back 10

liquefiable and non-liquefiable

Front 11

define liquefiable

Back 11

reversible solid, agar, thermoplastic

Front 12

define nonliquefiable

Back 12

thermoplastic, cooked meat, potato slices, egg media

Front 13

define synthetic media

Back 13

chemically defined media (highly pure organic and inorganic compounds)

Front 14

complex media

Back 14

(non-synthetic)- one ingredient, not chemically definable (Of plant, animal, or yeast extract)

Front 15

general purpose media

Back 15

used for broad-spectrum of microbes, non synthetic
examples: brain-heart infusion, tryptose soy agar, tryptose soy broth

Front 16

enrichment media

Back 16

complex organic substances: blood, serum, growth factors
used for fastidious organisms: streptococcus pneumoniae
requires blood- sterile horse, sheep, or rabbit

Front 17

selective and differential media

Back 17

designed for isolation and identification of specific groups of microbes from mixed populations

Front 18

selective media

Back 18

contains one or more inhibitory agent (dye, acid, antimicrobial agents)

Front 19

what does Mannitol Salt Agar inhibit

Back 19

human pathogens

Front 20

What does MAcConkey Agar/ Deoxycholate citrate agar inhibit?

Back 20

gram positive bacteria

Front 21

What does Sabourauds agar inhibit?

Back 21

bacteria

Front 22

differential medium

Back 22

allows for growth of several types BUT highlights differences(colony size, color, formation of gas, ppt)

Front 23

reducing media

Back 23

tyioglycollic acid or cystine absorbs oxygen/ slows penetration of oxygen THUS reducing availability REQUIRED for growing ANAEROBIC BACTERIA

Front 24

define carbohydrate fermentation

Back 24

sugars for fermentation, conversion to acids, pH indicator required for biochemical/Identification test

Front 25

define transport

Back 25

required for maintaining and preserving specimens for a period of time. examples: Stuarts and amies contain salts, buffers, and absorbants. Prevents cell destruction, pH changes, toxic substances NO GROWTH

Front 26

define assay

Back 26

tests effectiveness of antimicrobial agents i.e. disinfectants, antiseptics, cosmetics, etc.

Front 27

define enumeration

Back 27

used in industry: allows enumeration of organisms in milk, water, food, and soil samples

Front 28

define inspection of a culture

Back 28

observable growth

Front 29

define evaluation of a culture

Back 29

observing at various stages of growth

Front 30

macroscopically

Back 30

naked eye

Front 31

liquid media

Back 31

cloudiness, sediment, scum, or color change

Front 32

agar plate

Back 32

discrete isolated coloines, mass of clinging cells (fungi)

Front 33

Microscopically

Back 33

individual cells within a colony evidence of cellular morphology: size, shape, details of structure allows for identification

Front 34

what are the three aims when using a microscope?

Back 34

to provide adequate magnification, resolution, and clarity of the image

Front 35

Mount

Back 35

a sample on a glass slide, sits between a condenser and an objective lens

Front 36

3 factors to consider with the preparation of specimens

Back 36

1. condition of the specimen (living or preserved)
2. aims of examiner
3. type of microscope available

Front 37

What are the factors to consider while using living specimens?

Back 37

appear as near natural state as possible
media- suspended in water, broth, saline (allows for motility)
temperature- to maintain viability

Front 38

What are the advantages of using living specimens?

Back 38

quick and easy to prepare

Front 39

what are the disadvantages of using living organisms?

Back 39

no cover slip, susceptible to drying out, free to contamination

Front 40

What are the advantages of fixed preparations

Back 40

permanent mount, long term study

Front 41

when was the smear technique developed for fixed preparations?

Back 41

over a hundred years ago by Koch

Front 42

what is the disadvantage of fixed preparations?

Back 42

kills specimen

Front 43

what are the two types of dyes?

Back 43

basic (cationic) +ve charge
acidic (anionic) - ve charge

Front 44

what is the principle behind the dyes?

Back 44

opposites attract (polarity)

Front 45

what does positive staining do to the specimen?

Back 45

sticks to the specimen providing color

Front 46

negative staining does what to the specimen?

Back 46

settles around the specimen boundary forms a silhouette (stains the glass slide)

Front 47

what are the types of differential staining?

Back 47

gram stain
acid fast stain
endospore stain
capsule stain
flagellar stain

Front 48

what color is gram positive bacteria?

Back 48

purple/ blue

Front 49

what color is gram negative bacteria

Back 49

red/pink

Front 50

what color is acid-fast bacteria

Back 50

pink

Front 51

what color is non acid-fast bacteria

Back 51

blue

Front 52

what does endospore staining determine?

Back 52

distinguishes between bacteria that produce spores and those that do no

Front 53

what shape is coccoid?

Back 53

sperical (round)

Front 54

what shape is a round

Back 54

cylindrical

Front 55

what shape is spirilla

Back 55

spiral

Front 56

what shape is pleomorphic

Back 56

irregular shaped

Front 57

define magnification

Back 57

enlargement of an object

Front 58

define resolution

Back 58

degree to which detail is maintained in magnified image

Front 59

define resolving power

Back 59

closest spacing between 2 points where can be clearly seen as seperate entities

Front 60

brightfield microscope's are used for

Back 60

extensively used: necessary to view stained specimens

Front 61

what type of microscope is this:
specimen illuminated at one wavelength of light, observed by light at another wavelength. Uses fluorescent staining. No condenser. Objective lens focuses light. Useful diagnostic procedures: identify microorganisms

Back 61

epifluorescence microscope

Front 62

what kind of microscope is this:
eliminates need for staining. Achieve contrast between specimen and background.

Back 62

darkfield microscope

Front 63

what kind of microscope is this:
staining not required. View structures and living organisms

Back 63

phase contrast microscope

Front 64

what kind of microscope is this:
uses electrons, not a beam. Greater resolution. Higher magnifications

Back 64

electron microscope

Front 65

what are the two types of electron microscopes

Back 65

transmission EM and scanning EM

Front 66

what kind of microscope is this:
electrons pass through specimen. View ultrastructure or organisms

Back 66

transmission EM

Front 67

what kind of microscope is this:
electron beam scanned across surface of specimen: 3D image

Back 67

scanning EM