The Colorless Molecule O-Nitrophenyl Galactoside (ONPG) Can Be Used as an Artificial

question 28

Multiple Choice

The colorless molecule o-nitrophenyl galactoside (ONPG) can be used as an artificial substrate in assays of $\beta$ -gal in E. coli extracts. Which of the following statements is NOT true with respect to the use of ONPG?

• A) Hydrolysis of ONPG by \(\beta\)-gal produces yellow o-nitrophenol.
• B) o-nitrophenol can be measured with a spectrophotometer.
• C) Hydrolysis of ONPG by \(\beta\)-gal also releases colorless galactose.
• D) The o-nitrophenol moiety is blue and more suitable for use in solid media.
• E) None of the above.

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Definitions:

Semantic Memory

Pertains to a form of enduring memory that involves the ability to remember words, ideas, or figures, crucial for utilizing and comprehending language.

Consciously

In a way that involves awareness of one's own existence, sensations, thoughts, surroundings, etc.

Unconsciously

The process or condition of affecting or being influenced by something without conscious awareness or intent.

Korsakoff Syndrome

A chronic memory disorder caused by severe deficiency of thiamine (vitamin B1), most often associated with alcoholism.