snRNAs undergo specific post-transcriptional modifications, such as pseudouridinylylation and the addition of methyl groups. These modifications occur in__A__,  where they are directed by__B_.

#Question id: 9208

#Unit 9. Diversity of Life Forms

Which of the following threats to biodiversity is targeted at specific species rather than groups of species?

#Question id: 9209

#Unit 9. Diversity of Life Forms

Introduced species can have deleterious effects on biological communities by ________.

#Question id: 9210

#Unit 9. Diversity of Life Forms

Overharvesting encourages extinction and is most likely to affect ________.

#Question id: 9211

#Unit 9. Diversity of Life Forms

Of the following ecosystem types, which have been impacted the most by humans?

#Question id: 9212

#Unit 9. Diversity of Life Forms

Burning fossil fuels releases oxides of sulfur and nitrogen. These air pollutants can be responsible for ________.

#Question id: 9213

#Unit 9. Diversity of Life Forms

Suppose you attend a town meeting at which some experts tell the audience that they have performed a cost-benefit analysis of a proposed transit system that would probably reduce overall air pollution and fossil fuel consumption. The analysis, however, reveals that ticket prices will not cover the cost of operating the system when fuel, wages, and equipment are taken into account. As a biologist, you know that if ecosystem services had been included in the analysis, the experts might have arrived at a different answer. Why are ecosystem services rarely included in economic analyses?