Convert:

0.06 ml to ul

Convert: 

10 ul to ml

Convert:

940 ul to ml

Convert:

3.5 ml to ul

Capsule is

d. all of the above

True/ Flase

A " specific stain" is used to increse contrast so that morphology, size and arrrangement can be determined. 

True/ Flase

Basic dye will react with the surface of bacteria that is positively charged

I am using an autoclave machine to denature protein, degrade nucleic acid, and disrupt membrane. Which sterilization method is this?

a. Heat sterilization

b. Radiation sterlization

c. Filter sterlization

d. All of teh above

10.0ul= 0.01ml

CFU= (1x10⁴ cell/ml)x(0.01ml)= 100 CFU

The gram stain is __ stain based on the bacterial __ composition.

a. simple, membrane

b. simple, cell wall

c. differential, cell wall

d. negative, membrane

Fluid thioglycollate broth contains an indicator dye that turns ___ in the presence of

a. Pink, bacterial waste products

b. yellow, oxygen

c. Yellow, carbon dioxide

d. Pink, oxygen

There are ___ phases of bacterial growth in a batch culture, they occur in the following order

a. 4; log, stationary, death, lag

b. 4; lag, log, stationary, death

c. 3; lag, stationary, log

d. 2; log, stationary 

Filtration, as a sterilization technique, is typically used fro what kinds of samples?

a. fine powders

b. agar media

c. heat-tolerant liquids

d. heat-sensitive liquids

Bacteria that can respond by focusing their direation of travel toward or away from a chemical stimulus exhibit?

a. brownian motion

b. chemotaxis

c. motility

d. have many cilia

a. C. sporogenes

b. E. coli

c. B. megaterium

d. N. sicca

a. C. sporogenes

b. E. coli

c. N. sicca

d. B.megaterium

α- hemolysis: partial digestion

β- hemolysis: complete digestion

Υ- hemolysis: no digestion

You are performing a direct count on a bacterial sample. You dilute the sample as follows: 1:5,1:5, and 1:5. You then add the dye, load the counting chamber and count your cells. What is the final dilution factor of the series; what is the total dilution factor?

a. 5; 125

b. 2; 250

c. 5; 2500

d. 5; 250

Which technique can be used for sterilization when your container you wish to sterlize is heat- sensitve?

a. McFarlands standards

b. radiation

c. streak plate

d. filtration

Which reagent is used in Voges- Proskauer (VP) test to detect an oxidation of sugar into acid products or acetoin?

a. hydrogen peroxide

b. kovac's reagent

c. lugol's iodine

d. barritt's agent A and B

An unknonw species produces dark metallic colonies on EMB media plate. Identify the organism(s):

a. E. coli

b. S. aureus

c. P. aeruginosa

d. all of the above

When creating a turbidimetry standard graph, the dependent variable (y-axis) is:

a. time

b. bacterial concentration

c. optical density

d. transmittance

T/F 

a batch culture is a closed system where fresh nutrients are not added and the cells cannot maintain exponential growth for long

T/F

MAC is used to differentiate organisms based on their patterns of hemolysis

T/F 

Kohler illumination serves to achieve the highest possible resolution to view your specimen

T/F

An advantage of teh direct count quantification technique is that it count both live and dead cells

T/F 

Based on its name, one should expect S. pneumoniare to be a rod- shaped bacterium.

Below is a list of bacteral characteristics. These characteristics are based on the outcome of severl media tests. Use these lists to identify the bacterium used in each series of tests. Write the name (genus and species; genus abbreviation is acceptable if it follows the standard format) of the organism at the base of each list. 

Series of tests:

- no growth on MSA

- Growth on EMB: colorless colonies

- Growth on MAC: colorless colonies and media is yellow to light pink

Name of organism:

Gram (+): 

• thick cell wall
• stains violet 

1. Denature: @ 95°C breaking H-bonds apart 
2. Annealing: @ 64°C placing 3' primers down 
3. extensions: @ 72°C replicating and adding nucleotides 

T/F

Exoenzyme are used to degrade large polymers into smaller compounds

T/F

For the MR-VP text, E.coli is positive for MR and negative for VP, while E. aerogenes is positive for VP but negative for MR

T/F

Pink colonies growing on EMB are lactose fermenting colonies

T/F

MSA is selective for gram positive bacteria

a. anaerobic

b. facultative anaerobic

c. aerobic

d. microaerophille

T/F

The capsule stain utilizes both an acid dye and a basic dye to stain both the cell and the background

T/F

A working culture is a culture that is stored at  a temperrature that prevents microbial growth

T/F

The gram stain differentiates cell types based on their cell membrane lipid structure

T/F

Aseptic technique are important for preventing contamination of pure bacterial cultures

T/ F

E.coli is gram positive cocci

T/F

In a FTB, facultative, and aerotolerant anaerobes will grow through out the tube.

Reflect only viable bacteria:

1. Filtration

2. Standard plate count 

Count both live and dead bacteria:

1. Direct count

2. Turbidity

How does the absorbance value of a culture sample relate to the concentraton of bacteria within that sample?

a. the greater the absorbance the more bacteria are present

b. the greater the absorbance the less bacteria are present

c. there is no way to use the absorbance value to determine bacterial concentration

d. the greater than transmittance value the more bacterria are present

Bacteria that can respond by focusing their direction of travel toward or away from a chemical stimulus exhibit?

a. brownian motion

b. chemotaxis

c. motility

d. have many cilia

A complex media

a. Is one in which the exact contents are unknown

b. Is one in which the exact contents are known

c. Is one that allows only specific types of bacteria to grow. 

a. methylene blue and nigrosine

b. Metheylene blue stains the bacterria

nigrosine stains the background 

T/F

 A working culture is a culture that is stored at a temperature that prevents microbial growth. 

T/F

 Klebsiella has two membranes and a thin peptidoglycan layer, thus it is gram + bacteria

False 

has a thich cell wall and one membrane

T/F

Aseptic tecniques are important for preventing contamination of pure bacterial culture

List the dyes/reagents used in the gram stain in the correct order they are used and also name the dye respectively. 

a. Mordant

b. Counterstain

c. Decolorizer

d. Primary stain

a. Iodine [2nd]

b. Saffarin [4th]

c. 95% ethanol [3rd]

d. Crytal violet [1st]

Which of the following is NOT  a pure culture technique?

a. Streak plate

b. Spread plate

c. TSA slant tube

d. Pour plate

You want to dilute a broth culture of E. coli. You perform a serial dilution as follows: 

1:100, 1:100, 1:10, 1:5

What is the total dilution factor of the dilution series?

a. 100

b. 1000

c. 500

d. 500000

Which type of bacteria can survive in both oxygne free and oxygen rich environments?

a. Strict anerobes

b. Facultative anaerobes

c. Strict aerobes

d. Microaerophilles

alpha hemolysis: partial digestion

Beta hemolysis: complete digestion

1. Radiation= UV rays are used 

• for petri dishes

1. Heat= 15 PSI and 121°C ex. autoclave 

• for liquids