Exam 2 quiz 3

Question 1

Differential staining

Answer 1

involves the use of two contrasting stains which allow bacteria to be separated into groups

Question 2

mycobacterium

Answer 2

-slow growing
-arabinogalactan
-mycomembrane

Question 3

inner leaflet of mycomembrane

Answer 3

mycolic acid

Question 4

outer leaflet of mycomembrane

Answer 4

phenolic glycolipids

Question 5

what do phenolic glycolipids and mycolic acid form

Answer 5

a very hydrophobic environement

Question 6

Acid-fast stain

Answer 6

-used in mycobacterium

Question 7

primary stain in acid fast

Answer 7

carbolfuchsin (red stain) made in 5% phenol

Question 8

two methods for acid fast stain

Answer 8

-Ziehl-Neelson Mehtod (Hot method)
-Kinyoun Method (Cold method)

Question 9

Ziehl-Neelson method

Answer 9

-use steam heat
-stain on for five minutes and keep adding stain bc it will evaporate
-done in fue hood bc of phenolic fumes
-allow to cool before wash

Question 10

Kinyoun method

Answer 10

-carbofuchian that has a wetting agent added (tergitol)
-5 min incubation but do not need to continue adding
-dont need to do in fume hood

Question 11

decolorizer in acid-fast stain

Answer 11

5-10sec using acid alcohol
-3% HCl in 95% ehtanol
-goal is to see something gain/lose color

Question 12

Acid fast stain characters

Answer 12

-Carbofuchion wants to stay in hydrophobic mycomembrane
-primary stain more soluble in mycomembrane hydrophobic environment
-draws stain in

Question 13

non-acid fast characters

Answer 13

-primary stain is more soluble in decolorizer
-draws stain out
-colorless

Question 14

secondary stain of acid fast

Answer 14

-typically methylene blue
-red color if acid fast
-blue color if non-acid fast

Question 15

endospore layers

Answer 15

-exosporium
-spore coat
-outer membranes
-cortex
-inner membrane
-core

Question 16

endospore staining method

Answer 16

Schaffer-Fulton Method

Question 17

Schaffer-Fulton Method

Answer 17

-heat from a steam bath ideally
-can use a hot plate though

Question 18

primary stain of endospore stain

Answer 18

-Malachite green (weak stain)
-5 min incubation
-keep adding dye
-allow to cool before wash

Question 19

endospore stain decolorizer

Answer 19

just water! no strict time just look at the runoff

Question 20

if endospore then decolorizer..

Answer 20

-endospore locks in the stain so the water cant penetrate

Question 21

if nonendospore then decolorizer..

Answer 21

-stain washed out because the primary stain is weak

Question 22

Secondary stain in endospore stain

Answer 22

safranin, 2 mins