tools of the laboratory

Question 1

what is identification of microorganism?

Answer 1

to attach a name or identity to the microbe using information gathered from inspection and investigation.

Question 2

incubation of microorganism

Answer 2

inoculated media are placed in a controlled environment incubator to promote health

Question 3

inspection of microorganism

Answer 3

cultures are observed for the macroscopic appearance of growth and development

Question 4

isolation of microorganisms

Answer 4

some inoculation techniques can separate microbes to create isolated colonies that each contain a single type of microbe

Question 5

ability to enlarge objects

Answer 5

magnification

Question 6

ability to show detail

Answer 6

resolving power

Question 7

magnification in most microscopes results from an interaction between

Answer 7

visible light waves and the curvature of a lens

Question 8

of the final image is a product of the separate magnifying powers if the two lenses

Answer 8

total magnification

Question 9

what is the total magnification consist of

Answer 9

objective power x ocular power = total magnification

Question 10

the capacity to distinguish or separate two adjacent objects and depends on

Answer 10

resolution

Question 11

most widely used specimen is darker than surrounding field used for live and preserved stained specimens.

Answer 11

bright-field

Question 12

brightly illuminated specimens surrounded by darker=field used for live unstained specimens

Answer 12

dark-field

Question 13

transforms subtle changes in light waves passing through the specimens into differences in light intensity best for observing intracellular structures

Answer 13

phase-contrast

Question 14

modified microscope with an ultraviolet radiation source and filter uses dyes that emit visible light when bombard with shorter UV rays useful for diagnosing infections

Answer 14

fluorescence microscope

Question 15

uses a laser beam of light to scan the specimen integrates images to allow focus on multiple depths or planes

Answer 15

scanning confocal microscope

Question 16

forms an image with a beam of electrons that can be made to travel in wavelike patterns when accelerated to high speeds electron waves are 100,000 times shorter than waves of visible light magnification between 5,000x and 1,000,000x used to see viruses

Answer 16

electron microscope

Question 17

transmit electrons through the specimen

Answer 17

transmission electron microscope (TEM)

Question 18

provide detailed three-dimensional view

Answer 18

scanning electron microscope (SEM)

Question 19

what are dyes used for

Answer 19

to create contrast by imparting color

Question 20

cationic positively changed chromophore

Answer 20

basic dyes

Question 21

surfaces of microbes are negatively charged and attracted basic dyes

Answer 21

positive staining

Question 22

one dye is used revels shape size and arrangement

Answer 22

simple stains

Question 23

use a primary stain and a counterstain to distinguish cell types or parts

Answer 23

differential stains

Question 24

reveal certain cell parts not revealed by conventional methods capsule and flagellar stains

Answer 24

structural stains

Question 25

allow examination of characteristics of live cells size motility shape and arrangement

Answer 25

wet mounts and hanging drop mounts

Question 26

are made by drying and heating a film of specimen this smear is stained using dyes to permit visualization of cells or cell parts

Answer 26

fixed mounts

Question 27

anionic negatively charged chromophore

Answer 27

acidic dyes

Question 28

microbe repels dye the dye satins the background

Answer 28

negative staining

Question 29

in Gram stain Purple cells are

Answer 29

gram -positive

Question 30

in Gram stain Red cells are

Answer 30

gram- negative

Question 31

The 6 I's of culturing microbes

Answer 31

inoculation isolation incubation inspection information gathering identification

Question 32

introduction of a sample into s container of media to produce a culture of observable growth

Answer 32

inoculation

Question 33

separating one species from another

Answer 33

isolation

Question 34

under conditions that allow growth

Answer 34

incubation

Question 35

a consists of one species

Answer 35

colony

Question 36

this method works best if the spreading tool is resterilized after each of steps 1-3

Answer 36

streak plate techinque

Question 37

what do you check for in the inspection step

Answer 37

check for contaminates in the culture

Question 38

media can be classified according to three properties

Answer 38

physical state chemical composition functional type

Question 39

liquid semisolid and solid

Answer 39

physical state

Question 40

synthetic and complex

Answer 40

chemical composition

Question 41

general purpose enriched selective differential anaerobic transport assay enumeration

Answer 41

functional type

Question 42

what are the physical states of media

Answer 42

liquid semisolid solid

Question 43

does not solidify

Answer 43

liquid

Question 44

contains solidifying agent

Answer 44

semisolid

Question 45

firm surface for colony formation

Answer 45

solid

Question 46

what is the most commonly used solidifying agent

Answer 46

agar it provides framework to hold moisture and nutrients

Question 47

contains pure organic and inorganic compounds in an exact chemical formula

Answer 47

synthetic

Question 48

contains at least one ingredient that is not chemically definable

Answer 48

complex or nonsynthetic

Question 49

grows a broad range of microbes usually non synthetic

Answer 49

general purpose media

Question 50

contains complex organic substances such as blood serum hemoglobin or special growth factors required by fastidious microbes

Answer 50

enriched media

Question 51

contains one or more agents that inhibit growth of some microbes and encourage growth if the desired microbes

Answer 51

selective media

Question 52

allows growth if several types if microbes and displays visible differences among those microbes

Answer 52

differential media

Question 53

liquid medium containing beef extract and peptone

Answer 53

nutrient broth

Question 54

solid media containing beef extract peptone and agar

Answer 54

nutrient agar

Question 55

contains sugars that can be fermented converted to acids and a pH indicator

Answer 55

carbohydrate fermentation medium