Use the Following Information to Answer the Question

question 52

Multiple Choice

Use the following information to answer the question.
Poliovirus is an RNA virus of the picornavirus group, which uses its RNA as mRNA. The RNA genome has a 5′ RNA cap instead of a 5′ methyl-G cap. This is followed by a non-translated leader sequence and then a single long protein-coding region (~7,000 nucleotides) followed by a poly-A tail. Infected cells were incubated with radioactive amino acids and viral proteins were isolated. After a short incubation with radioactive amino acids only very long viral proteins were seen, while longer periods of labeling result in several short polypeptides of different lengths.
Which of the following conclusions is most consistent with the results described?

• A) Host cell ribosomes translate the viral coding region and poly-A tail at different times resulting in the different populations of proteins.
• B) The RNA is first translated into a single long protein, which is then cleaved into shorter ones.
• C) The RNA is translated into short polypeptides, which are then assembled into large complexes.
• D) The large radioactive polypeptides are coded by the host, whereas the short ones are coded for by the virus.

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Definitions:

Type II Error

A statistical error that occurs when a false null hypothesis is not rejected, also known as a "false negative" finding.

Two-Tailed Hypothesis

A form of statistical hypothesis testing where the alternative hypothesis specifies that the parameter of interest differs from the null hypothesis.

Population Mean

The average value of all the members of a set or population, denoting the central tendency.

Null Hypothesis

An assumption made for a statistical test that there is no significant difference or effect, to be tested against the alternative hypothesis.