Lab exam 1

Question 1

If the objective lenses of a microscope can be changed without losing focus on the specimen, they are said to be

Answer 1

parfocal

Question 2

The distance between the two eyepieces of the binocular microscope is called the ________________ distance

Answer 2

interpupillary distance

Question 3

Microscopes are carried by holding the _______ and _____________

Answer 3

arm and base

Question 4

The part of the microscope that connects the eyepiece to the nosepiece is the __________________.

Answer 4

body tube

Question 5

The part of the microscope that contains magnifying lenses to look through is the ____________.

Answer 5

ocular

Question 6

The part of the microscope that controls the amount of light that passes through the specimen is the

Answer 6

iris diaphragm

Question 7

The part of the microscope that contains lenses with different powers of magnification is the

Answer 7

nosepiece

Question 8

The part of the microscope that moves the stage quickly up and down and is used to focus the image under low power is the

Answer 8

coarse adjustment

Question 9

This objective is used with oil.

Answer 9

100x

Question 10

Prior to staining, smears of microorganisms are heat-fixed in order to

Answer 10

kill the microorganism and attach it to the slide

Question 11

The procedure in which a single stain is used to visualize microorganisms is called __________________staining.

Answer 11

simple

Question 12

Thin films of bacteria that have been air-dried onto a glass microscope slide are called

Answer 12

bacterial smear

Question 13

The cell wall of a bacteria is __________________________ charged as it relates to staining.

Answer 13

negative

Question 14

The background is stained and not the bacteria in this staining procedure

Answer 14

negative stain

Question 15

The Gram staining procedure differentiates bacteria based on the chemical composition of which cell structure?

Answer 15

cell wall

Question 16

After the counter stain has been added, gram positive organisms are stained _______________ and gram negative organisms are stained ___________________________ .

Answer 16

purple, pink

Question 17

If a microbiology lab technician left the safarnin out of the Gram stain procedure, what would be the result?

Answer 17

gram-positive cells would be purple and gram-negative are colorless

Question 18

The Gram staining procedure is an example of:

Answer 18

differential staining

Question 19

In the Gram staining procedure, the mordant is

Answer 19

iodine

Question 20

Where do gloves go when done with the lab?

Answer 20

bio hazard trash

Question 21

What should you wipe lab table with before and after lab?

Answer 21

10% chlorine bleach

Question 22

Where does broken glass go?

Answer 22

sharps box

Question 23

What is the preferred method of decontaminating microbiological waste?

Answer 23

the autoclave

Question 24

BSL-1

Answer 24

nonpathogenic organisms

Question 25

BSL-2

Answer 25

organisms that present a moderate environmental and/ or health hazard

Question 26

BSL-3

Answer 26

organisms are of local or exotic origin and are associated with respiratory transmission

Question 27

BSL-4

Answer 27

high prob. of organisms causing lethal infection

Question 28

What temp does the autoclave have to be at?

Answer 28

121 Celcius for 15 minutes

Question 29

streak plate technique

Answer 29

bacterial dilutions occur on the plate, used to isolate a mixed culture to a pure culture

Question 30

spread plate

Answer 30

bacterial dilutions occur in the test tube, isolate mixed cultures to a pure culture based on serial dilutions

Question 31

How do you prepare a sterile work area?

Answer 31

decontaminate with ethanol and light bunsen burner, sterilize insulator

Question 32

acidic stains

Answer 32

stain alkaline structure
bind to positively charged components like proteins
(eosin, Nigrosin

Question 33

basic stains

Answer 33

more common, stain acidic structures
bind to negatively charged cell parts like cell wall
(methylene blue, safarnin

Question 34

Kinds of special stains

Answer 34

negative, flagellar, fluroscent

Question 35

cocci

Answer 35

spherical

Question 36

bacili

Answer 36

rod shape

Question 37

spirals

Answer 37

curved walls

Question 38

vibrious

Answer 38

slightly curved rods

Question 39

Endospore stain

Answer 39

1. Prep smear
2. Add methylene blue
3. Rinse with water
4. blot slide with bibulos water
5. view with objective lenses

Question 40

negative stain

Answer 40

1. Place congo red in 2 separate circles
2. using a flamed inoculating needle, pick up bacillus subitilis and stir into congo red
3. scrape material from teeth with toothpick and stir into second drop of congo red
4. air dry
5. flood with acid alcohol until it turns blue
6. air dry
7. view with lenses