Why Would It Be Important for the Kirby-Bauer Disc Diffusion

question 50

Multiple Choice

Why would it be important for the Kirby-Bauer disc diffusion test to use a standard concentration (number of cells in the sample) of each of the bacterial strains being tested?

• A)Antibiotics only work within a narrow range of cell concentrations.If you use a concentration that is too low or too high,you will get inaccurate measurements of the zone of inhibition.
• B)Antibiotic resistance is usually only manifested by bacteria that have achieved a very high concentration (i.e.,they are in the very end of the stationary phase of the growth curve).It's important to use bacteria specifically at this particular point for disc diffusion testing.
• C)If you were to use one strain that was stationary phase (high concentration,replicating very slowly or not at all),and another strain that was just beginning log phase (low concentration but replicating quickly),you could see dramatically different results in the disc diffusion test.This could skew your interpretations of resistance/susceptibility.
• D)Growth on the Mueller-Hinton agar plates utilized is very sensitive to the phase of the growth curve the bacteria are in when they are placed on the plate.If they are not in the log phase when they are placed on the plate,they will not grow and the test will be worthless.

Distinguish between functional and dysfunctional team roles.

Understand the principles of effective teamwork and its significance in business success.

Understand the impact of hidden agendas on group dynamics and collaboration.

Recognize the importance of focusing on team objectives over individual priorities during collaboration.

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Definitions:

Differential-compound

Refers to a type of compound wound DC generator or motor that combines both series and shunt windings to achieve specific electrical characteristics.

Cumulative-compound

Refers to a type of DC generator where both series and shunt field windings add their magnetic fluxes to produce the total output voltage.

Shunt Field

A coil wound with small wire and having many turns designed to be connected in parallel with the armature of a DC machine.

Series Field

A winding of large wire and few turns designed to be connected in series with the armature of a DC machine.