Enumerating the Viable and Total Cell Concentration of a Population

question 86

Essay

Enumerating the viable and total cell concentration of a population of a microbial isolate can be a laborious task for a microbiologist, especially when studying the same isolate for several years. It is often more practical to determine the relationship between optical density (OD) and cell concentration. Once this relationship (determined by a standard curve) is determined, the OD of an isolate in a broth can be used to determine the populationʹs concentration. Why must a standard curve be prepared for each isolate when using OD measurements to determine cell concentration? Also describe an experiment that would generate this type of standard curve.

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Definitions:

Reasonable Value

A fair market price or level of compensation that would be deemed equitable under normal circumstances.

Gratuitous Promise

A promise for which no consideration is given or required in return, often unenforceable without a deed or under specific legal conditions.

Consideration

In contract law, consideration refers to the value (such as money, a service, or a promise) that is given in exchange for a contractual obligation from the other party.

Illusory Contract

An agreement that fails to bind one party due to vague or unenforceable terms, making it appear to be a contract only in illusion.