25. Which of the following experimental designs would provide the most robust evidence for the hypothesis that high-intensity ultrasound from bats serves as a specific trigger to inhibit moth flight? (A) Electrophysiological recording of moth motor neurons while mechanically stimulating the wing muscles. (B) Field observation of wild moths using high-speed infrared cameras while broadcasting ultrasonic pulses at frequencies and decibels mimicking hunting bats. (C) Qualitative observation of bat-moth interactions in a cave system to determine the percentage of successful strikes. (D) Laboratory trials comparing moth flight patterns when exposed to three-dimensional physical models of predators versus non-predatory insects. (E) Statistical analysis of moth population densities in regions with varying bat activity to correlate survival with flight cessation habits.

7. 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 by the virus.

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