3-5

Question 1

what is a basic stain?

Answer 1

+ charged dyes
stain bacterial cells (have a negative charge)

DO NOT STAIN SLIDE (has a positive charge)

Question 2

what is an acidic stain?

Answer 2

• charged dyes
  stain slide/background (has + charge)

DO NOT STAIN BACTERIAL CELLS (has - charge)

Question 3

what are some characteristics of simple staining?

Answer 3

1. use only one dye
2. all cells stain color of chosen dye
3. determines cell size, morphology, and arrangement
4. typical stains used
   methylene blue
   crystal violet
   safranin

Question 4

what do simple stains tells us?

Answer 4

size
shape
arrangement

Question 5

how many and what are the arrangements of coccus?

Answer 5

5 circular
1. diplococci (Cocci that remain in pairs after dividing are called diplococci)

2. streptococci (Cocci that remain in chains after dividing are called streptococci)
3. tetrad (Cocci that divide in two planes and remain in groups of four are called tetrads)
4. Sarcinae (Cocci that divide in three planes and remain in groups cube like groups of eight are called sarcinae)
5. Staphylococci (Cocci that divide in multiple planes and form grape like clusters or sheets are called staphylococci)

Question 6

how many and what are the arrangements bacillus?

Answer 6

4 rod

1. single bacillus (Most bacilli appear as single rods)
2. Diplobacilli (appear in pairs after division.)
3. Streptobacilli (appar in chains after division)
4. Coccobacillus (Some bacilli are so short and fat that they look like cocci and are referred to as coccobacilli)

Question 7

how many and what are the arrangements of spirilla?

Answer 7

3 (have one or more twists)

1. Vibrio (looks like a coma)
2. Spirillum (one curve)
3. Spirochete (many curves)

Question 8

what are some other shapes of bacteria?

Answer 8

star shaped

rectangle shape

Question 9

what does washing a slide with soap and water do?

Answer 9

removes oil and grease

Question 10

why should one flame a slide after washing it?

Answer 10

removes any remaining oil and oil from handling

Question 11

why should one use a small drop of water and small amount of bacteria?

Answer 11

enable smear to dry with in a few minutes

see single layer of cell (tiny amount of bacteria)

Question 12

why is it necessary to heat fix?

Answer 12

1. allow cells to adhere to slide
2. kill bacteria
3. coagulate cytoplasmic proteins (make them more visible)

Question 13

what do we dry the slide with?

Answer 13

bibulous paper

Question 14

what is a chromogen?

Answer 14

colored molecule

Question 15

what is a chromophore?

Answer 15

portion of chromogen that gives it its color

a chromogen can have multiple chromophores

Question 16

what is the auxochrome?

Answer 16

charged portion of chromogen and allows it to act as a dye