Mcbc 2010 - Chapter 03: Microbiology By Jacqueline G. Black 6Th Edition

Front 1

freeze-fracturing

Back 1

technique in which a cell is first frozen and then broken with a knife so that the fracture reveals structures inside the cell when observed by electron microscope

Front 2

heat fixation

Back 2

Technique in which air-dried smears are passed through an open flame so that organisms are killed, adhere better to the slide, and take up dye more easily

Front 3

active site

Back 3

Area on the surface of an enzyme to which its substrate binds

Front 4

flagellar staining

Back 4

A technique for observing flagella by coating the surfaces of flagella with a dye or metal such as silver

Front 5

iris diaphragm

Back 5

adjustable device in a microscope that controls the amount of light passing through the specimen

Front 6

transmission

Back 6

The passage of light through an object

Front 7

condenser

Back 7

Device in a microscope that converges light beams so that they will pass through the specimen

Front 8

parfocal

Back 8

For a microscope, remaining in approximate focus when minor focus adjustments are made

Front 9

differential stain

Back 9

Use of two or more dyes to differentiate among bacterial species or to distinguish various structures of an organism; for example, the Gram stain

Front 10

index of refraction

Back 10

A measure of the amount that light rays bend when passing from one medium to another

Front 11

atomic force microscope (AFM)

Back 11

Advanced member of the family of scanning tunneling microscopes, allowing three-dimensional views of structures from atomic size to about 1 mm

Front 12

hanging drop

Back 12

A special type of wet mount often used with dark-field illumination to study motility of organisms

Front 13

binocular

Back 13

Referring to a light microscope having two eyepieces (oculars)

Front 14

freeze-etching

Back 14

Technique in which water is evaporated under vacuum from the freeze-fractured surface of a specimen before an observation with electron microscopy

Front 15

absorption

Back 15

Process in which light rays are neither passed through nor reflected off an object but are retained and either transformed to another form of energy or used in biological processes

Front 16

monocular

Back 16

Refers to a light microsciope having one eyepiece (ocular)

Front 17

fluorescence microscopy

Back 17

use of ultraviolet light in a microscope to excite molecules so that they release light of different colors

Front 18

Schaeffer-Fulton spore staining

Back 18

A differential stain used to make endospires easier to visualize

Front 19

immersion oil

Back 19

Substance used to avoid refraction at a glass-air interface when examining objects through a microscope

Front 20

microscopy

Back 20

The technology for making very small things visible to the unaided eye

Front 21

fluorescent antibody staining

Back 21

procedure in fluorescence microscopy that uses a fluorochrome attached to antibodies to detect the presence of an antigen

Front 22

anionic dye

Back 22

(also called acidic dye) An ionic compound, used for staining bacteria, in which the negative ion imparts the color

Front 23

phosphorescence

Back 23

Continued emission of light by an object when light rays no longer strike it

Front 24

fluorescence

Back 24

Emission of light of one color when irradiated with another, shorter wavelength of light

Front 25

compound light microscope

Back 25

A light microscope with more than one lens

Front 26

TEM
(transmission electron microscope)

Back 26

Type of electron microscope used to study internal structures of cells; very thin slices of specimens are used

Front 27

refraction

Back 27

The bending of light as it passes from one medium to another medium of different density

Front 28

mordant

Back 28

A chemical that helps a stain adhere to the cell or cell structure

Front 29

ocular micrometer

Back 29

A glass disk with an inscribed scale that is placed inside the eyepiece of a microscope; used to measure the actual size of an object being viewed

Front 30

electron microscope

Back 30

Microscope that uses a beam of electrons rather than a beam of light and electromagnets instaed of glass lenses to produce an image

Front 31

wet mount

Back 31

Microscopy technique in which a drop of fluid containing the organisms (often living) is placed on a slide

Front 32

Ziehl-Neelsen acid-fast stain

Back 32

A differential stain for organisms that are not decolorized by acid in alcohol, such as the bacteria that cause Hansen's disease (leprosy) and tuberculosis

Front 33

mechanical stage

Back 33

Attachment to a microscope stage that holds the slide and allows precise control in moving the slide

Front 34

Gram stain

Back 34

A differential stain that uses crystal violet, iodine, alcohol, and safranin to differentiate bacteria. Gram-positive bacteria stain dark purple; Gram-negative ones stain pink/red

Front 35

resolving power

Back 35

A numerical measure of the resolution of an optical instrument

Front 36

dark-field illumination

Back 36

In light microscopy, the light that is refracted from an object rather than passing through it, resulting in a bright image on a dark background

Front 37

cationic dye

Back 37

(also called basic dye) An ionic compound, used for staining bacteria, in which the positive ion imparts the color

Front 38

STM
(scanning tunneling microscope)

Back 38

Also called scanning probe microscope; type of microscope in which electrons tunnel into each other's clouds, can show individual molecules, live specimens, and work underwater

Front 39

simple stain

Back 39

A single dye used to reveal basic cell shapes and arrangements

Front 40

SEM
(Scanning Electron Microscope)

Back 40

Type of electron microscope used to study the surfaces of a specimen

Front 41

coarse adjustment

Back 41

Focusing mechanism of a microscope that rapidly changes the distance between the objective lens and the specimen

Front 42

Nomarski microscopy

Back 42

Differential interference contrast microscopy; utilizes differences in refractive index to visualize structures, producing a nearly three-dimensional image

Front 43

micrometer

Back 43

(mm) Unit of measure equal to 0.000001 m or 10 ^-6 m; formerly called a micron (m)

Front 44

shadow casting

Back 44

The coating of electron microscopy specimens with a heavy metal, such as gold or palladium, to create a three-dimensional effect

Front 45

Angstrom (A)

Back 45

Unit of measurement equal to 0.0000000001 m, or 10210 m. No longer officially recognized

Front 46

numerical aperature

Back 46

The widest cone of light that can enter a lens

Front 47

reflection

Back 47

The bounding of light off an object

Front 48

nanometer

Back 48

(nm) Unit of measure equal to 0.000000001 m or 10 ^- 9 m; formerly called a millimicron (mm)

Front 49

body tube

Back 49

Microscope part that conveys an image from the objective to the eyepiece

Front 50

light microscopy

Back 50

The use of any type of microscope that uses visible light to make specimens observable

Front 51

objective lens

Back 51

lens in a microscope closest to the specimen that creates an enlarged image of the object viewed

Front 52

phase-contrast microscopy

Back 52

Use of a microscope having a condenser that accentuates small differences in the refractive index of various structures within the cell

Front 53

luminescence

Back 53

Process in which absorbed light rays are reemitted at longer wavelengths

Front 54

bright-field illumination

Back 54

illumination produced by the passage of visible light through the condenser of a light microscope

Front 55

diffraction

Back 55

Phenomenon in which light waves, as they pass through a small opening, are broken up into bands of different wavelengths

Front 56

ocular lens

Back 56

Lens in the microscope that further magnifies the image created by the objective lens

Front 57

smear

Back 57

A thin layer of liquid specimen spread out on a microscopic slide

Front 58

fine adjustment

Back 58

Focusing mechanism of a microscope that very slowly changes the distance between the objective lens and the specimen

Front 59

electron micrograph

Back 59

A "photograph" of an image taken with an electron microscope

Front 60

resolution

Back 60

The ability of an optical device to show two items as separate and discrete entities rather than a fuzzily overlapped image

Front 61

stain

Back 61

(also called dye) A molecule that can bind to a structure and give it color

Front 62

total magnification

Back 62

obtained by multiplying the magnifying power of the objective lens by the magnifying power of the ocular lens

Front 63

negative staining

Back 63

technique of staining the background around a specimen, leaving the specimen clear and unstained