A Series of Experiments Is Being Conducted to Determine the Structure

question 14

Multiple Choice

A series of experiments is being conducted to determine the structure and function of different types of bacterial RNA.  Cultures of Staphylococcus aureus are exposed to chemicals that lyse the bacterial cells, and the RNA molecules are then extracted.  A specific RNA consisting of 90 nucleotides is purified for further analysis.  It is found to contain high amounts of chemically modified bases such as dihydrouridine, pseudouridine, and ribothymidine, and its secondary structure arises from base pairing within the chain.  Which of the following is the most likely composition of the 3'-end of this molecule?

• A)AUG
• B)CCA
• C)Methylguanosine triphosphate
• D)Poly-A
• E)TATA
• F)UAG

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Definitions:

Reliability

Reliability refers to the degree to which an assessment tool produces stable and consistent results over time.

Validity

The extent to which a test, instrument, or procedure actually measures what it is intended to measure, reflecting the accuracy of the results.

Regression

A return to an earlier or less advanced state or form of behavior, often as a defense mechanism in psychology.

Content Validity

The extent to which a test measures all aspects of the concept it intends to measure.