In Purifying Proteins by Column Chromatography, Elution Can Be Performed

question 87

Multiple Choice

In purifying proteins by column chromatography, elution can be performed in different ways, depending on the type of matrix. For example, bound proteins can be eluted by gradually increasing or decreasing salt concentration in the solution applied to the column. For which of the following matrices do you think increasing and decreasing salt concentration, respectively, are used for elution?

• A) Ion-exchange; hydrophobic
• B) Affinity; ion-exchange
• C) Hydrophobic; affinity
• D) Hydrophobic; ion-exchange
• E) Ion-exchange; gel-filtration

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Definitions:

Imperfect Competitor

A firm that has some control over the market price of its product because the product is differentiated and there are few substitutes.

Wage Rate

The amount of money paid to an employee per unit of time, often hourly or annually, for their labor.

Wage Rate

The amount of money paid to an employee for a specified quantity of work, usually expressed per hour or year.

Perfect Competitor

A theoretical market structure where many firms sell identical products, entry and exit are easy, and no single buyer or seller can influence the market price.