Microbio Lab Mid Term

Front 1

Spherical organism?

Back 1

Cocci

Front 2

Rod shaped organism?

Back 2

Bacilli

Front 3

Spiral shaped organism?

Back 3

Helicoidal

Front 4

Forms pairs of round organisms

Back 4

Diplococci

Front 5

Forms chains of round organisms

Back 5

Streptococci

Front 6

Groups of 4 round organisms

Back 6

Tetracocci

Front 7

Forms random clusters of round organisms

Back 7

Staphylococci

Front 8

Forms square patters of round organisms

Back 8

Sarcinae

Front 9

Cationic dyes used?

Back 9

Methylene blue and crystal violet

Front 10

Anionic dyes used

Back 10

acid fuschin, congo red, nigrosin

Front 11

fat soluble dyes

Back 11

sudan black

Front 12

water insoluble dyes

Back 12

india ink

Front 13

dyes used for negative stains

Back 13

india ink and nigrosin

Front 14

dyes used for simple stains

Back 14

methylene blue and crystal violet

Front 15

types of differential stains

Back 15

gram stain and acid fast

Front 16

difference in cell wall between gram + and -

Back 16

gram + have higher peptidoglycan content and lower lipid

Front 17

steps and dyes used for gram stain

Back 17

1. Crystal violet
2. iodine
3.ethanol
4.saffranin

Front 18

cell wall structure of acid fast positive

Back 18

have a high wax content

Front 19

acid fast steps and dyes

Back 19

1. carbol fuschin
2.steam
3. acid alcohol
4. methylene blue

Front 20

3 genera of spore forming bacteria

Back 20

Bacillus - aerobic, gram + rod
Clostridium - anerobic, gram + rod
Sporsarcinae - Cocci

Front 21

2 genera of acid fast + organisms

Back 21

Mycobacterium- T.B. and leprae
Nocardia

Front 22

spore staining steps

Back 22

1. Malachite green
2. steam
3. water
4. safranin

Front 23

Tube Media

Pour -
Broth -
Deep -
Slant -
Fermentation broth -

Back 23

Pour - 15-20mL liquid agar poured into dish
Broth - 5-7mL of liquid media
Deep - 5-7mL solidified media
Slant - 5-7mL solidified media at angle
Fermentation broth - broth with Durham tube added

Front 24

Selective Media
&
Differential media

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Selective Media - limits growth of certain type of organism

Differential media - used to determine characteristics of organisms

Front 25

PEA ?

Back 25

Phenylethly alcohol agar - selects for gram +

Front 26

DES ?

Back 26

desoxycholate agar - Selective and differential. selects for gram -
tests for lactase, if present will produce acid and pull dye into cell turning red

Front 27

EMB ?

Back 27

Eosin methylene blue - Selective and differential. selects for gram -
differentiates between lactase +/-
If present and colonies have dark blue-black centers or a metalic green shine (E. coli) then organism is mixed acid fermentor.
If pink - purple centers then butanediol fermentors

Front 28

blood agar ?

Back 28

defferential.
determines blood hemolysis.
Almost, Best, Garbage
A - alpha, partial hemolysis
B- beta - complete hemolysis
G - gamma - no hemolysis

Front 29

Starch agar ?

Back 29

tests for presence of amylase. if present will hydrolyse starch into simple sugars. iodine added and will not be on the edges of + colonies

Front 30

milk agar ?

Back 30

tests for enzyme Caseinase that hydrolyzes casein into amino acids. plate will be clear around + colonies

Front 31

lipase plate

Back 31

tests for lipase, if present hydrolyzes fat into glycerol and fatty acids. if + turns blue

Front 32

sugar fermentation tubes

Back 32

determines fermentation of particular sugar. if sugar fermentation is present a color change towards yellow will occur

Yellow = acid
Yellow + gas = acid and gas
Red = alkaline

Front 33

methyl red (MR)
E. Coli + or - ?

Back 33

Tests for mixed acid fermentor.
if + pH drops below 5.1 and stays red.
reaction = HCOOH to CO2 and H2

Front 34

Voges - Proskauer (VP)

Back 34

Tests for 2,3 butanediol fermentors
Reaction = CHOOH to acetly methly carbinol (AMC, or acetoin) Uses VP1(alpha napthol) and VP2 (KOH). positive result = red color

Front 35

catalase

Back 35

tests for catalase. add hydrogen peroxide. if + result, H2O2 will be broken down into 2H2O and O2 giving gas bubbles

Front 36

oxidase

Back 36

uses dimethyl-p-phenylenediamine hydrochloride ( bullshit) to turn dark blue / black if positive

Front 37

nitrate

Back 37

tests for ability to reduce nitrate.
Add Nitrate 1(sulfanilic acid) and nitrate 2(dimehtyl-alpha-napthylamine) to tube. If red then +, if not add zinc. if turns red after zinc, -. if not red after zinc , +

Front 38

tryptophan (indole)

Back 38

tests for tryptophanase. reaction = tryptophan to pyruvic acid and indole.
add kovac's reagent (p-dimethylaminobenzaldehyde, amyl or butyl alcohol, and HCL). If red then + and indole present

Front 39

Urea

Back 39

Tests for urease. Reaction = urea to ammonia and CO2. turns red if +

Front 40

hydrogen sulfide production

Back 40

tests for cysteine desulfurase. if present sulfur side chains removed from cysteine to produce H2S which forms black precipitate if +

Front 41

(SIM) Sulfur Indole Motility

Back 41

H2S production = black = +
Kovac's reagent turns red = indole +
growth away from inoculation line = +

Front 42

simmons citrate

Back 42

tests for ability to use citrate as only carbon source. Growth or deep blue color = +

Front 43

Phenylalanine (PPA)

Back 43

tests for phenylalanase. turns phenylalanine into PPA(phenylpyruvic acid) and NH3. reacts with ferric chloride to give green color for +

Front 44

Litmus milk

Back 44

tests for lactose fermentation.
Acid reaction = pink liquid
Acid curd = pink solid
Reduction = white
alkaline = blue liquid
peptonization/proteolysis - clear brown or amber liquid

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I M V C
E. coli +/- +/- +/- +/-
E. A. +/- +/- +/- +/-

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E. coli + + - -
E. A. - - + +

Front 46

Motility test

Back 46

Tetrazolium cholrida turns red if growth. Growth away from inoculation line = motility

Front 47

rules for plate count

Back 47

1. must have between 30-300 colonies
2. write in dilution factors
3. left to right = x * dilution factor
4. right to left = x* 1/ dilution factor