Lab 3: Staining

Question 1

acid fast bacteria are resistant to gram staining due to waxy cell surface caused by unusual complex lipids known as what?

Answer 1

mycolic acids

Question 2

how do we overcome the problems of mycolic acids?

Answer 2

moderate heats and detergents to break down lipid components of call wall and allow dye penetration

Question 3

carboxylic acid on mycolic acids react with _______ dye/

Answer 3

fushin

Question 4

What are the three steps of acid fast stains?

Answer 4

1. carbolfucshin stain allowed to penetrate into cell
2. decolorizing agent applied
3. counterstain added

Question 5

What is used in acid fast staining to enhance penetration of carbolfucshion?

Answer 5

phenol

Question 6

What is the counterstain added in acid fast staining?

Answer 6

methylene blue

Question 7

What is the decolorizing agent used in acid fast staining?

Answer 7

acid-alcohol

Question 8

What is the chemical makeup of acid-alcohol?

Answer 8

3% HCl and 95% ethanol

Question 9

________: structured extracellular matriculates composed of polysaccharides?

Answer 9

capsules

Question 10

Capsule producing strains often being more virulent. T or F?

Answer 10

T

Question 11

Can capsule be stained though methods involving heat. T or F?

Answer 11

T

Question 12

_______: stain the background but no the cells

Answer 12

negative stains

Question 13

______: is precipitated onto the filament which increases diameter through coating the flagella

Answer 13

mordant

Question 14

What do you call a cell that has a flagella coming out of one end?

Answer 14

monotrichous

Question 15

What do you call a cell that has multiple flagella coming out of one end?

Answer 15

lophotrichous

Question 16

What do you call a cell that has flagella coming out of both ends?

Answer 16

amphitrichous

Question 17

What do you call a cell that has flagella extending from all sides?

Answer 17

petrichous

Question 18

_______: dormant form of bacteria resistant to hostile environments

Answer 18

endospores

Question 19

What is it about the endospore outer covering that causes the cells resistance to staining?

Answer 19

keratin

Question 20

What is the effect of malachite green ?

Answer 20

forces the dye into the cell by heating

Question 21

vegetive cells are decolorized with water and stained with __________________

Answer 21

spore safranin counterstain

Question 22

________: the spore at the end of an endospore

Answer 22

terminal spore

Question 23

_________: the spore at the almost end of the endospore

Answer 23

subterminal

Question 24

__________: the spore is in the middle of the spore?

Answer 24

central

Question 25

What are the steps of a flagella stain?

Answer 25

1. get prepared slide
2. place on staining rail
3. break ampule dropper and apply it onto cell
4. let sit
5. Whirl pool bath
6. Let dry for 45 min
7. Look at flagella under microscope

Question 26

What are the steps of acid fast stain?

Answer 26

1. Create a mixed slide
2. use toothpick to break up mixture
3. heat fix
4. add drops of carbolfucshin stain
5. rinse
6. continue rinsing and add 2-3 drops of acid-alcohol to decolorize
7. counterstain with methylene blue
8. rinse off excess with water

Question 27

What are the possible results of the acid fast stain?

Answer 27

non acid fast bacteria will be blue/purple

acid fast bacteria will be red

Question 28

what are the steps of an endospore stain?

Answer 28

1. create a smear plate
2. cover the slide with paper towel and add lactate green
3. steam for 10 minutes and continue to add drops of malachite green
4. remove paper towel and rinse
5. counterstain with spore safranin
6. rinse
7. dry

Question 29

what will the results of the endospore stain be?

Answer 29

there will be red vegetative cells and green endospores