chapter 3

Question 1

identification

Answer 1

attaching a name/ identity to a microbe

Question 2

inoculation

Answer 2

sample is placed in a container with media that will support its growth (plates, tubes, flasks)

Question 3

information

Answer 3

additional tests for function and characteristics of sample; can provide specific info for unique microbes

Question 4

incubation

Answer 4

inoculated media are placed in an environment where a culture will develop, and a growth of microbes

Question 5

inspection

Answer 5

organisms are examined for appearance and for basic details (cell type and shape)

Question 6

isolation

Answer 6

separation of microbes to create colonies

Question 7

3 techniques for isolation

Answer 7

wet mounts, hanging drops, fixed mounts

Question 8

properties to classify media

Answer 8

physical state, chemical state, functional type

Question 9

types of media

Answer 9

liquid, semisolid, solid

Question 10

Why is agar a useful substance

Answer 10

it is not a nutrient source for most microbes

Question 11

synthetic media

Answer 11

Pure organic and inorganic compounds; chemically defined

Question 12

complex/non-synthetic media

Answer 12

one ingredient that cannot be chemically definable

Question 13

general purpose media

Answer 13

grows a broad range of microbes

Question 14

selective media

Answer 14

one microbe is favored and encouraged to grow

Question 15

differential media

Answer 15

growth of several distinguishable microbes

Question 16

carbohydrate fermentation media

Answer 16

sugars that can be fermented, converted to acids, and used by a pH indicator

Question 17

Pure culture

Answer 17

culture with only one organism

Question 18

mixed culture

Answer 18

culture with multiple species, still distinguishable

Question 19

contaminated culture

Answer 19

unwanted microorganisms or contaminants

Question 20

magnification

Answer 20

enlarging objects

Question 21

resolving power

Answer 21

ability to show detail

Question 22

magnification results from

Answer 22

curvature of lens and lightwaves

Question 23

what type of lightwaves are optimal

Answer 23

short lightwaves

Question 24

refraction

Answer 24

the bending of a wave as it enters a new medium at an angle

Question 25

real image

Answer 25

a copy of an object formed at the point where light rays actually meet

Question 26

virtual image

Answer 26

a reflected optical image

Question 27

numerical aperture of lens

Answer 27

0.1 to 1.25

Question 28

purpose of using oil for oil immersion

Answer 28

increases resolving power

Question 29

what makes a resolution better

Answer 29

shorter wavelength and larger numerical aperture

Question 30

bright field microscope

Answer 30

specimen is darker than background

Question 31

dark field microscope

Answer 31

background is darker than specimen

Question 32

phase contrast microscope

Answer 32

subtle changes in lightwaves pass through specimen in different intensity; can see intracellular structures

Question 33

fluorescence microscope

Answer 33

uses UV rays; good for diagnosing infections

Question 34

TEM microscope

Answer 34

electrons through specimen, thin specimen slices, 2D interior

Question 35

SEM microscope

Answer 35

bounces off surface, whole specimen, 3D exterior/surface

Question 36

basic dyes

Answer 36

cationic, positively charged chromophore

Question 37

positive staining

Answer 37

surfaces of microbes are negatively charged and attract basic dyes

Question 38

acidic staining

Answer 38

anionic, negatively charged chromophore

Question 39

negative staining

Answer 39

staining the background instead of the cell; microbe repels dye

Question 40

simple stain

Answer 40

use of a single basic dye

Question 41

differential stain

Answer 41

two or more dyes used to distinguish between different organisms/ cell parts

Question 42

structural stain

Answer 42

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