Lab Practical 1

Question 1

Why is it necessary to heat fix bacterial cells

Answer 1

to get bacteria to stick to the glass

Question 2

a common stain that is used in simple staining

Answer 2

crystal violet

Question 3

give two reasons for cooling the slide before applying the stain

Answer 3

prevent cracking and prevent participate

Question 4

the stain used in a Negative stain is

Answer 4

Nigrosin

Question 5

Why is Nigrosin called the negative stain

Answer 5

because it makes ligh structures dark and dark structures light

Question 6

the easiest staining procedure is

Answer 6

a simple stane

Question 7

why is the simple stain valuable

Answer 7

identify organisms/inhibit growth

Question 8

the type of mount that you use in the lab to study organisms for a short period of time is

Answer 8

temporary mount

Question 9

why should you flame the inoculation loop while using it

Answer 9

to sterilize it

Question 10

the microscope used in the labratory is a

Answer 10

compound binocular light microscope

Question 11

the ability of a microscope to reveal fine detail is known as

Answer 11

greater resolution

Question 12

the 10X eyepiece used in combination with a 45X objective produces a magnification of

Answer 12

450X

Question 13

another name for the 100X objective lens is

Answer 13

oil immersion objective

Question 14

when putting the microscope away which objecive should be in place

Answer 14

low power objective

Question 15

if the letter e is moved to the right, in which direction does it appear to move in the field of view

Answer 15

left

Question 16

what part of the microscope regulates the amount of light enering

Answer 16

the condenser

Question 17

what part of the microscope is used if some focusing adjustment is needed with high power

Answer 17

find adjustment knobs

Question 18

identify the person who was first to observe microorganisms

Answer 18

van leewenhoek

Question 19

which of the folowing cannot be seen with your labratory microscope

Answer 19

viruses

Question 20

the primary stain in an acid fast stain is

Answer 20

carbolfuschin

Question 21

the counterstain is

Answer 21

methelyne blue

Question 22

an example of an acid fast positive organism is

Answer 22

Mycobacterium

Question 23

acid fast positive organism stian what color

Answer 23

red

Question 24

the decolorizer used in an acid fast stain is

Answer 24

95% acid alcohol

Question 25

what enables the acid fast bacteria to retain the primary stain

Answer 25

heating

Question 26

acid fast negative organisms stain what color

Answer 26

blue/green

Question 27

a colony with a form such as O is described as

Answer 27

cocci

Question 28

when idenfying organisms according to growth what precaution should be taken after inocculating the tubes

Answer 28

shaking tube

Question 29

can you tell celllular contents or cell shape from cellular morphology?

Answer 29

cell shape

Question 30

a culture in which you have many diifferent types are associated togehter is considere to be

Answer 30

mixed

Question 31

the single most important bacteriological stain is

Answer 31

gram stain

Question 32

the counter stain used in a gram stain is

Answer 32

safranin

Question 33

idetify the decolorizing agent in a gram stain

Answer 33

95% ethyl alcohol

Question 34

gram negative bacteria stain what color

Answer 34

red

Question 35

gram positive bacteria stain what color

Answer 35

purple

Question 36

the most critical part of the gram staining procedure is

Answer 36

95% ethyl alchohol

Question 37

what techinique used to maintain sterility and avoid contamination is called

Answer 37

aseptic technique

Question 38

turbidity can best be seen on what time of plate

Answer 38

broth

Question 39

what is the purpose of flaming your loop

Answer 39

to sterilize

Question 40

the primary stain used in the endospore procedure is

Answer 40

malchite green

Question 41

what color do the endospores stain

Answer 41

green

Question 42

why do you steam the endospore stain

Answer 42

to put cracks in the spore wall to allow dye in

Question 43

another name for the endospore stainis

Answer 43

shaeffer-fulton method

Question 44

what counter stain is used in an endospore stain

Answer 44

safranin

Question 45

two genera most noted for production of endospores

Answer 45

bacillis and clostridium

Question 46

an endospore is a vegetative or dormant cell

Answer 46

dormant cell

Question 47

the color produced which indicates an organism uses citrate as a carbon source

Answer 47

blue

Question 48

E. Coli is citrate positive or negative

Answer 48

negative

Question 49

the steps of a gram stain

Answer 49

1. apply crystal violet for 30 seconds 2. add iodine grams for 30 seconds 3. rinse with 95% ethyl alcohol until majority of stain runs off (20 seconds) 4. ) counterstain with safranin for 30 seconds