The Plate Count Method Was Used to Estimate the Number

question 60

Multiple Choice

The plate count method was used to estimate the number of bacteria in a culture over time.Serial dilutions were made of culture samples at various time points.A 0.1 ml portion of the 10⁻⁶ dilution was spread over the surface of a nutrient agar plate for each time point.The plates were incubated for 24 hrs and the colony forming units (CFU) were counted on each plate.A total of 45 colonies were counted on the plate for the 30 minute time point.What was the cell population for this time point?

• A)4.5 X 10⁴ CFU/ml
• B)4.5 X 10⁵ CFU/ml
• C)4.5 X 10⁶ CFU/ml
• D)4.5 X 10⁷ CFU/ml
• E)4.5 X 10⁸ CFU/ml

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Definitions:

Equal Satisfaction

A principle in consumer choice theory that suggests consumers allocate their resources to maximize satisfaction or utility.

Indifference

A state where a consumer has no preference between two or more choices.

Utility

An economic term referring to the total satisfaction received from consuming a good or service.

Indifference Curve

A graphical representation showing different combinations of goods or services among which a consumer is indifferent, implying no preference for one combination over another, given their utility or satisfaction remains constant.