Chapter 4

Question 1

coccus

Answer 1

sphere

Question 2

bacillus

Answer 2

rod

Question 3

three main shapes of bacteria

Answer 3

coccus, bacillus, spiral

Question 4

small drop of liquid spread on the slide

Answer 4

liquid culture

Question 5

small colony piece mixed with a drop of water

Answer 5

solid culture

Question 6

Air drying purpose

Answer 6

preserves the microorganisms shape and arrangement

Question 7

purpose of heat fixation

Answer 7

kills microorganism and causes it to adhere to slide

Question 8

the dyes used in staining are usually

Answer 8

salts

Question 9

a salt contains

Answer 9

a positively charged cation and a negatively charged anion

Question 10

the colored portion of the dye

Answer 10

chromophore

Question 11

what is the chromophores purpose

Answer 11

binds to chemicals in cell structures via covalent/ionic bonding

Question 12

procedures that only use one dye that is basic such as crystal violet or methylene blue

Answer 12

simple stain

Question 13

what is the purpose of simple staining

Answer 13

to identify the shape, structure, and arrangement of bacteria

Question 14

simple stain steps

Answer 14

1. flood smear with dye for 30-60 sec
2. rinse with water
3. blot dry

Question 15

uses two or more dyes

Answer 15

differential stain

Question 16

purpose of differential stain

Answer 16

to distinguish different cells, structures or gram type

Question 17

who developed gram stain

Answer 17

hans gram

Question 18

steps to gram stain

Answer 18

1. apply the primary stain crystal violet (all cells with be purple)
2. flood smear with mordant like iodine (traps color into the peptidoglycan of gram + cells)
3. rinse away with decolorizing agent (washes away the dye from the top of the gram - cell)
4. apply counter stain safranin (provides contrasting color to primary stain)

Question 19

removes water from liquid crystal violet turning it into solid crystals

Answer 19

mordant

Question 20

color of gram +

Answer 20

purple

Question 21

color of gram -

Answer 21

pink

Question 22

gram stain works significantly better on

Answer 22

younger cells

Question 23

waxy substance on some bacteria

Answer 23

mycolic acid

Question 24

some myobacterium causes

Answer 24

tuberculosis and leprosy

Question 25

Steps to acid fast staining

Answer 25

1. primary stain, flood smear with carbolfushsin under heat which will melt the solid wax layer 2. rinse with decolorizing agent, which will remove stain from non acid fast cells 3. counter stain with methylene blue

Question 26

results of acid fast stain

Answer 26

myobacterium (acid fast) = red non acid fast = blue

Question 27

what bacteria causes endospores

Answer 27

bacillus and clostridium

Question 28

endospore bacteria causes diseases such as

Answer 28

anthrax, gangrene, tetanus

Question 29

developed to specifically stain endospores

Answer 29

schaeffer-fulton or endospore stain

Question 30

steps to endospore staining

Answer 30

1. primary stain with malachite green with heat (heat opens up pores in endospore) 2. decolorizing agent which causes vegetative cells to be clear and endospore to be green 3. counterstain with safranin (turns vegetative cells red)

Question 31

what is the decolorizing agent in endospore staining

Answer 31

water

Question 32

stains used to reveal specific microbial structures such as capsuels

Answer 32

negative staining

Question 33

staining steps for a negative stain

Answer 33

1. use primary dye to stain bacteria (crystal violet) this will stain bacteria except the capsule 2. stain background with an acidic or - charged dye like india ink (will repel the cell membrane and capsule)

Question 34

negative stain results

Answer 34

background = pink bacteria = purple capsule = white halo

Question 35

acidic dye in negative stain

Answer 35

india ink

Question 35

primary stain in negative stain

Answer 35

crystal violet

Question 36

staining that targets bacteria and flagella

Answer 36

flagellar staining

Question 37

in flagellar staining what is mixed together to be used as primary stain

Answer 37

primary stain and a mordant

Question 38

combination of primary stain and mordant allows the dye to be

Answer 38

less soluble, increases size and colorizes flagella

Question 39

the ability to distinguish two objects or points that are close together

Answer 39

resolution or resolving power

Question 40

difference in the intensity of two objects or the object and its background

Answer 40

contrast

Question 41

describe a simple microscope

Answer 41

- one lens - less magnifying power, less resolving power -cannot distinguish between two objects

Question 42

compound microscope characteristics

Answer 42

- series of lenses - have objective and ocular lenses - has a condenser

Question 43

narrows beam of light from the illumination exit and focuses it directly on speciman

Answer 43

condenser

Question 44

total magnification

Answer 44

objective lens x ocular lens

Question 45

used to view bacteria, viruses, internal cellular structure, molecules, large atoms

Answer 45

electron microscopy

Question 46

a beam of electrons is transmitted through the speciman

Answer 46

electron transmission microscopy

Question 47

In TEM, electrons interact with what structures

Answer 47

internal (ribosomes, or inclusions)

Question 48

a beam of electrons scans the surface of the speciman

Answer 48

scanning transmission microscopy

Question 49

describe SEM

Answer 49

- coated with gold or platinum and placed into vacuum - used to view morphology or 3d surface of speciman

Question 50

describe TEM

Answer 50

- speciman is dehdryated, chemically fixed, and embedded into plastic and placed in a vacuum

Question 51

the science of classifying and naming organisms

Answer 51

taxonomy

Question 52

the assigning of organisms to taxa based on similarities

Answer 52

classification

Question 53

determining that an isolated organism belongs to a particular taxon or group

Answer 53

identification

Question 54

rules of naming an organism

Answer 54

nomenclature