prep of smears and simple staining

Question 1

simple stain

Answer 1

Staining procedures that only use one stain

Question 2

basic stain

Answer 2

if the chromophore is a positive ion like methylne blue than it is basic

Question 3

acid stain (negative)

Answer 3

if it is a negative ion , stains only the background not the organism

Question 4

chromophore?

Answer 4

the ion that is colored

Question 5

simple stains can test for?

Answer 5

morphology, size, and arrangement

Question 6

what is the purpose of fixation?

Answer 6

to kill the bacteria

Question 7

heat fixation vs chemical fixation

Answer 7

heat fixation make cells stick to the slide
preserves morphology but not structures within the cells

chemical fixation by covering smear with 95% methanol
penetrates cells and reacts with cellular components

Question 8

steps on creating a smear from solid media

Answer 8

1. create two circles with a marking pencil on slides
2. place one or two loopful of water on the slide
3. with sterlized loop transfer a small amount of culture on the slide and mix it with the water
4. allow to air dry
5. heat fix

Question 9

creating a smear from liquid media

Answer 9

1. create two circles with a marking pencil on slides
2. place 2 or 3 loopfuls of the liquid culture on the slide with sterlized loop
3. spread the bacteria
4. air dry
5. chemical fixation with 95% ethanol

Question 10

why must you air dry before heat fixing?

Answer 10

prevent splatter

Question 11

what causes a smear to be too thin? and what issues arise from that

Answer 11

can become over decolorized and there won’t enough cells to view

Question 12

what causes a smear to be too thick?

Answer 12

too much organism can be hard to differ and can cause over colorization