問題一覧
1
What is an example of gram - cells ?
E.coli, serratia
2
Which stain has acid fusion as the primary, no mordant or decolorizer, Congo red as the counter stain, and it’s not heat fixed ?
negative capsule
3
When you first focus on an object, you start with _____ focus then you adjust with _____ focus
course, fine
4
What does a mordant do ?
forms a stable complex with crystal violet allowing the stain to adhere to the G+ cell wall and G- cell outer membrane
5
After endospore staining what color are the spores ?
green
6
Which stain has carbon fuchsin as primary, heat as the mordant, acid alcohol as the decolorizer, methylene blue as counter stain, and its heat fixed ?
acid fast
7
What is an example of gram + cell ?
staphylococcus aureus
8
What genus of bacteria are acid fast ?
mycobacterium
9
List a stain that it negatively charged (acidic)?
Congo red, nigrosin
10
What is the purpose of simple stain ?
tells you Shape and arrangement of bacteria
11
Which stain has crystal violet as it’s primary, gram’s iodine as the mordant, ethyl alcohol as the decolorizer, safranin as the counter stain and its heat fixed ?
gram stain
12
What color are the vegetative cells ?
red-pink
13
Why are they acid fast ?
cell wall contains a high amount of mycolic acid
14
What color is the background ?
blue
15
What is the function of the condenser ?
collect and direct the light from the light source to the slide being studied
16
What 2 genera are endospore formers ?
bacillus and clostridium
17
What color are vegetative cells ?
red-pink
18
What is resolution ?
ability to see 2 objects separate
19
What is the difference between simple and differential staining ?
simple shows only shape and differential shows shape and distinguishes between two different species
20
List two reasons to heat fix a bacterial slide
bacteria sticks to the slide , kills bacteria
21
Why must you clean the table top before and after the lab time ?
to prevent cross contamination of all material
22
What is the field of view ?
the area you can see through the microscope lenses
23
What are the differences in gram + and gram - ?
cell wall
24
What color are gram + cells
blue-purple
25
Why does negative stain give a more accurate measure of cell size ?
we don’t hear fix and we don’t distort the cell
26
Which stain has malachite green as primary, heat as the mordant, no decolorizer, safranin as the counter stain, and its heat fixed ?
endospore
27
What are the magnifications and total magnifications of the lenses ?
scanning: 4x-40x, low dry: 10x-100x, high dry: 40x-400x, oil immersion: 100x-1000x
28
What is the first thing to be done when entering the lab ?
clean table and wash your hands
29
What color are non-acid fast cells ?
blue
30
What is the function of the diaphragm ?
controls the amount of light which reaches the slide by opening or closing it
31
Which stain has methylene blue and is heat fixed ?
simple
32
What color are acid fast cells ?
red-pink
33
What color are gram - cells ?
red-pink
34
Why do most biological stains have a positive charge (basic) ?
gram (+): teichoic acid, gram (-): lipopolysaccaride
35
After negative staining what color is the capsule ?
colorless
36
Define parfocal
doesn’t need any course adjustment and should automatically be focused after high dry