Lab Test #2

Front 1

Dye solutions/stains

Back 1

used to color cells, or their background, thus making them more visible to the human eye.

Front 2

Chromophores

Back 2

Stains are composed of color-bearing ions in an aqueous solution. These carry either positive or negative charge.

Front 3

Basic stains/dyes

Back 3

have a positive charged (cationic) chromophores.

Front 4

Acidic stains/dyes

Back 4

have negatively charged (anionic) chromophores.

Front 5

negative

Back 5

Bacteria have a slightly ________ charge on their surface. This causes cationic chromophores to be attracted to the bacterial cell. (Unlike charges do what?)

Front 6

much easier to prepare

slides are less expensive and disposable

able to go to oil

Back 6

What are the advantages of using the wet mount over the hanging drop techniques?

Front 7

Anionic chromophores

Back 7

________ __________ on the other hand will not stain the baterial cell itself but will stain the background instead. (Like charges do what?)

Front 8

drys out

tends to dry out much faster than the hanging drop slide

limits the amount of time you can observe the motility and activity of an organism

Back 8

What are the disadvantages of a wet mount technique?

Front 9

Motility

Back 9

self-directed movement

Front 10

much more labor intensive both in preparation and cost

must be cleaned everytime rather than disposing of them.

Back 10

What are the disadvantages of hanging drop technique?

Front 11

don't dry out

able to see motility and activity of the organism

Back 11

What are the advantages of using the hanging drop technique?

Front 12

flagella, cilia, and pseudopods

Back 12

How can microorganisms get around or move?

Front 13

self-directed movement

Back 13

The ability to have _____ ________ ________ confers a distinct advantage over nonmotile organisms.

Front 14

positive chemotaxis

negative chemotaxis

Back 14

A truly motile microbe can move toward a chemical stimulus, such as source of nutrient (________ _________) or away from a harmful substance (_________ __________).

Front 15

allowing a motile organism to more easily penetrate our defenses, such as mucus membranes

more readily spread throughout the body.

Back 15

What does motility imply for pathogens?

Front 16

kinetic energy

Back 16

What causes brownian motion?

Front 17

Brownian motion or movement

Back 17

non-directional, vibratory movement of small particles or cells, due to collisions with water molecules.

Front 18

motile

Back 18

Proteus mirabilis

motile or nonmotile?

Front 19

nonmotile

Back 19

Staph. aureus

motile or nonmotile?

Front 20

disinfectant dish

Back 20

Where should you put the depression slides from the hanging drop technique after we are done with them?

Front 21

dissecting needle

Back 21

What should we use to remove the coverslip from the depression slide?

Front 22

15 mins

Back 22

How long should we leave the depression slides in the disinfectant dish?

Front 23

gloves

Back 23

What should you be wearing when you remove the depression slide from disinfectant dish, while cleaning, and placing it on the rack?

Front 24

Differential staining technique

Back 24

___________ ________ _________ involve more than one type of stain and differentiate (distinguish) btwn various types of bacteria and/or bring out specific structures.

Front 25

Christian Gram

Back 25

Who developed the gram stain?

Front 26

cell wall

Back 26

Bacteria satin differently with the Gram stain technique because of differences in their _____ _____ structure.

Front 27

gram positive

Back 27

What bacteria would have cell walls composed of thick layer of peptidoglycan and teichoic acid?

Front 28

gram negative

Back 28

What bacteria would have a much thinner layer of peptidoglycan, no teichoic acid and a high concentration of various lipids?

Front 29

Gram-variable

Back 29

Some bacteria do not stain uniformly with the gram stain technique and are known as _____ ________.

Front 30

18-24

Back 30

What is the optimal time for the growth of an organism for the gram stain technique?

Front 31

age

Back 31

The ____ of the culture can also affect the results of a gram stain. Older cultures of gram positive bacteria tend to decolorize rapidly resulting in a false gram negative reaction.

Front 32

gram variable

Back 32

If the bacterial smear is too thick it may result in uneven staining and decolorizing and have the appearance of a ______ _________.

Front 33

gram +

Back 33

cell wall: peptidoglycan

Front 34

gram -

Back 34

Lipid A

Front 35

crystal violet

Back 35

What is the name for the primary stain in the gram stain technique?

Front 36

1 min

Back 36

How long do you leave the CV on for in gram stain?

Front 37

gram's iodine

Back 37

What is the mordant in the gram stain?

Front 38

Mordant

Back 38

anything that anchors the 1' stain.

Front 39

ethyl alcohol

Back 39

What is the decolorizing agent in the gram stain technique?

Front 40

decolorizing

Back 40

As soon as color stops running from the smear, stop the ___________ process by rinsing the slide with tap water.

Front 41

safranin

Back 41

What is the counterstain for the gram stain?

Front 42

1 min

Back 42

How long do you leave the safranin on for in the gram stain?

Front 43

bibulous paper

Back 43

Blot the slide with _________ _____ and observe the slide under oil.

Front 44

purple
pink to red

Back 44

A gram-positive cell will appear ______ and a gram-negative will appear _____ depending on how long you leave the safranin on for.

Front 45

mycobacterium and nocardia

Back 45

The acid fast stain technique (another differential stain) is primarily used in the identification of pathogenic bacteria in the genera ________________ and ________.

Front 46

tuburculosis
leprosy
organ failure

Back 46

The genus mycobacterium contains species that are significant human pathogens mycobacterium tuberculosis, the causative agent of ___________, Mycobacterium leprae, the causative agent of ________ and increasingly, in immunocompromised individuals, Mycobacterium avium-intracellulare, that can rapidly disseminate throughout the body causing _______ ________ and death.

Front 47

Nocardia asteroids

Back 47

__________ __________, a common inhabitant of soil and water, can cause opportunistic infections in the lungs and skin of humans.

Front 48

mycolic acid

Back 48

What these organisms have in common and what distinguishes them from other bacteria is their cell walls contain large amounts of a waxy lipid substance called ________ _____.

Front 49

carbolfuchsin

Back 49

It is believed that __________, the primary stain in acid fast staining, forms a complex with the mycolic acid in the cell walls of acid fast bacteria making them more resistant to decolorization with acid alcohol after staining with carbolfushin.

Front 50

vegatative cell

Back 50

The metabolically active, reproducing form of a bacterial cell is termed the ___________ ______.

Front 51

sporogenesis

spore

Back 51

Certain genera of bacteria, by the process of ___________, are able to package their genetic information in an extremely resistant form, called a _______, and thus survive environmental conditions that would easily kill the vegatative cell.

Front 52

endospore

Back 52

The spore is formed within the vegatative cell and is termed an __________.

Front 53

exospore

Back 53

Upon the death and disintegration of the vegetative cell the endospore is released and becomes a free spore sometimes referred to as an _________.

Front 54

reproductive

Back 54

Sporogenesis, in bacteria, is not a __________ process.

Front 55

germinate

Back 55

One vegetative cell will produce one spore and the vegetative cell has to rupture to release the spore. When environment condidtion improve, the spore will __________ to form one vegetative cell.

Front 56

survival

Back 56

The formation of spores is a _________ mechanism.

Front 57

spore
resistant

Back 57

Their thick ______ coat and low metabolic activity (they essentially dormant) renders spores extremely _________ to drying, heat, radiation, and toxic chemicals.

Front 58

Clostridium
Bacillus

Back 58

What are two medically significant genera of bacteria that are able to produce spores?

Front 59

disinfection

biological weapons

Back 59

The ability of the spores of pathogenic species within these genera to survive normal __________ measures has profound implications for the food and healthcare industries as well as concerns of their use as __________ _______ of war or terrorism.

Front 60

glycocalyx

Back 60

Many bacteria have a gelatinous coating exterior to their cell wall called a ___________.

Front 61

thickness
chemical composition

Back 61

The glycocalyx can vary in _________ and _________ composition among different species of bacteria.

Front 62

slime layer

Back 62

Some bacteria have a diffuse, amorphous glycocalyx layer termed _______ _______.

Front 63

capsule

Back 63

Others have much thicker glycocalyx that is tightly bound to the cell termed a _______.

Front 64

Streptococcus pneumoniae

Back 64

What pathogen produces capsules?

Front 65

adding osmotic barrier
inhibits phagocytosis
adherence
storage of nutrients

Back 65

List four ways in which a capsule can confer an advantage to the bacterium producing it.

Front 66

destroy or shrink capsule

Back 66

Why wasn't any heat used with this technique?