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Microbiology Lab Practical
Microbiology Lab Practical
54
Microbiology
Undergraduate 2
04/13/2015

Additional Microbiology Flashcards

 


 

Cards

Term
[image]
Definition

Microscope occular. 

Eye peice (usually 10x magnification)

Term
[image]
Definition

Microscope objective

we use 100x for oil immersion

Term
[image]
Definition

Microscope condensor

directs light towards the objective lens in bright feild micsopcopy

 

Term
Resolution 
Definition

resolving power.

expressed as d (the smallest distance between two objects that can be seen as seperate)
small d= better resolution

d=λ/2NA

Term
[image]
Definition
cocci
Term
[image]
Definition
Rod (Bacilli)
Term
[image]
Definition

Diplococci 

divide in one plane

Term
[image]
Definition

Steptococci

Divide in one plane

Term
[image]
Definition
Tetracocci (tetreads)
Divide in two planes
Term
[image]
Definition
Staphylococci
Term
[image]
Definition

Sarcinae 

divide in three planes 

Term
[image]
Definition
coccobacillus
Term
Cationic dyes 
Definition

basic, positively charged chromophore

Ex: Methylene Blue and Crystal Violet

Term
Anionic Dyes
Definition

acidic, negativley charged chromophore

EX: Acid Fuchsin, Congo Red, Nigrosin

Term
Fat soluble Dye
Definition

no charge

Ex: Sudan black

 

Term
Insoluble dye 
Definition

Water insoluble

EX: India ink 

Term
[image]
Definition

Negative stain

size and shape

stains the background, not the cell.

(NOT DARK FEILD MICROSCOPY)

two dyes used:

-Nigrosin  (negative so reppeled by neg charge on bacteria)

-India ink (insuluble so doe snot penetrate cell)

Term
Negative stain procedure 
Definition

-put the dots of bacteria and dye then spread with another slide at 45 degree angle

DO NOT RINSE OR HEAT FIX

Term
[image]
Definition

Simple stain 

shape

one dye used to stain all cells the same color

Cationic dyes (methelyne blue and crystal violet)

Term
[image]
Definition

Gram stain

Differential: based on cell wall

Dye: Crystal violet

Mordant: Iodine

Decolorizer: Ethanol

Counter stain: Safranin

Gram+ Purple

Gram- pink 

Term
[image]
Definition

Acid fast stain

Differential: based on cell wall (Mycolic wax content)

Primary stain: Carbol Fuchsin 

STEAM

Decolorizer: Acid alcohol

Counterstain: Methylene Blue (cationic)

(High wax) ACID FAST+  RED

ACID FAST- BLUE

Term
[image]
Definition

Spore stain

structural (specialized)

Primary stain: Malachite Green

STEAM

Decolorizer: water

Counterstain: Safranin

Endospore: green in center of pink 

sporangium: pink

free spore: green oval bodies 

 

Term
[image]
Definition

AGAR:

Broth: liquid

Slant: Solid

Deep: solid 

Term
PEA
Definition

Phenylethyl Alcohol Agar

Selects for growth of gram+

Term
[image]
Definition

Desoxycholate Agar DES 

selective and differential

selects for growth of gram-

red colony: lactose+

nonred colony: Lactose-

Term
[image]
Definition

Eosin Methylene Blue (EMB)
SELECTIVE AND DIFFERENTIAL

selects for gram-

Differentiation:

Dark colony: lactose ferm & produce alot of acid 

pink colony: lacrtos ferm

no color absorbed: lact-

Term
[image]
Definition

Blood agar plate 

differentiates based on reactions to blood

"BAG"

A: Beta hemolysis 

b: Alpha hemolysis

c: Gamma hemolysis

 

Term
Starch Agar
Definition

tests for amylase

Indicator: iodine (added after growth)

colorless around colony: +

purple around colony: -

(because iodine+starch=purple so this means th amylase was not there to hydrolize the starch)

Term
[image]
Definition

tests for caseinase (Hydrolizes casein-Milk)

A: -

B: +

Term
[image]
Definition

tests for lipase

Blue dye intensifies: + (lower pH)

no blue intensification:-

Term
[image]
Definition

Phenol Sugar Fermentation and Durham tube

(the first tube shows the control)

yellow: ferm+

lt orange-red:ferm-

Gas in tube: Gas prodctuction

Term
[image]
Definition

Methyl Red

tests for mixed acid fermentors

indicator: Methly red (after growth)

dye stays red: + pH under 5.1

dye turns yellow: -

Term
[image]
Definition

VP

test for 2,3 butanediol fermenter

Reagents=

Barrit's reagents.

VP1: Alpha-nahthol

VP2: KOH

red on top:+

no red:-

Term
[image]
Definition

Catalase

differential

detects catalase

bubbles:+

no bubbles:-

 

Term
[image]
Definition

Oxidase

differential: detects oxidase whih removes hydrogen

aromatic ameine used

 (oxidase reagents added after growth)

colorless:-

dark purple/red to dark blue:+

Term
[image]
Definition

Nitrate broth

Differentail: tests for nitrate reductase

red w/o zinc: +

red w/ zinc: -

Never red: +

Term
[image]
Definition

Tryptone

differential tests for indole (to see if tryptonase is present because it turns tryptone into indole )

Indicator: Kovac's reagent

red top: indole+ so tryptonase +

yellow top: indole- so tryptonase -



 

 

Term
[image]
Definition

Urea

Differential

detects urease 

indicator: phenol red

Red to cerise=+

yellow to orange=-

Term
[image]
Definition

SIM

Sulfur Indole Motility 

H2S positive: Black

Indole+: Kovac's reagent turns red after addition

Motility+: growth away from stab line 

Term
[image]
Definition

Simmons citrate slant

differential

detects for the use of citrate as sole carbon source 

starts green 

No growth:- (reagardless of color change)

Growth and Blue color: +

Term
[image]
Definition

differential

 tests for presence of phenylalanase

indicator: ferric chloride added after growth

green: +

no color change to ferric chloride: -

 

Term
Litmus milk results 
Definition
[image]
Term
[image]
Definition

Gelatin

detects gelitinase 

resolidification: -

no resolidification: +

Term
[image]
Definition

OF GLUCOSE 

Tests to determine if a bacteria can use glucose in an oxidative (aerobic) or fermentative  (anerobic) condition.

On open tube and one closed (added oil)

Results:

-OPEN CLOSED: Incompletly Oxidative (O)

-OPEN CLOSED: Strictly Fermentation (F)

-OPEN CLOSED: Strictly Oxidative

-OPEN CLOSED: Faculative 


Term
Total mag
Definition
Ocular x Objectice
Term
[image]
Definition

KIA
tests for the ability to ferment glucose and/or lactose, tests H2S production and can be used to test for gas production.

 Results:

>Red slant/Red butt: Gluc- Lac- H2S- 

>Red slant/ yellow butt: Gluc+ Lac- H2S- 

>Yellow slant/ Yellow butt: Gluc+ Lac+ H2S- 

>Black Red slant tip and gas: Gluc+ Lac- H2S+ (Salmonella Proteus) 
> Black yellow slantand gas: Gluc+ Lac+ H2S+

 

*NOTE: IF THERE IS GAS AT THE BOTTOM (AND ONLY THE VERY TIP TOP IS RED) THEN IT IS LAC+

Term
WHAT IS THE ONLY POSITIVE IN THE UREASE TEST?
Definition
Proteus
Term
Reagents for VP Test
Definition

Barrit's reagents.

VP1: Alpha-nahthol

VP2: KOH

Term
[image]
Definition
Seratia
Term
[image]
Definition
Set up for direct microscope count

usually performed in milk. Much quicker than a standard plate count

Term
Determining Actual Bacterial Count in DMC
Definition

1.Count the number of organisms seen in a single microscopic field of view

2.Count 9 additional fields of view

3.Add the number of organisms and divide the total by 10 to determine the average

4.Multiple the average by the Microscopic Factor previously determined

# Bacteria/ml = Average # bacteria X MF

Term
COAGULASE
Definition

Bacteria incubated in a small tube of plasma overnight.

If the plasma becomes clumpy or solidfies, the coagulase+

ONLY VALID ON GRAM+ STAPHYLOCCUS LIKE BACTERIA

Term
Gram + Cocci
Definition
  • Staphylococcus-
    • Aureus (Manitol/caogulase/DNase +)
    • Epidermis (Manitol/caogulase/DNase -)
  • Streptococcus
    • Pneumoniae (Alpha hemolysis)
    • Pyorgenes (Beta hemolysis) 
Term
Gram + bacterias 
Definition
  • Corynebacterium
  • lactobacillus
  • Sporosarcina
  • Micrococcus
  • Staphylococcus
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