One group of ecologists has suggested that producers are limited by competition for resources, primary consumers (herbivores) are limited by predation, and secondary consumers (carnivores) are limited by food. If this were true, at which of the following trophic levels would one expect to find substantial evidence for competitive exclusion?

#Question id: 4121

#Unit 3. Fundamental Processes

The transition from the closed to the open complex involves structural changes in the enzyme and the opening of the DNA double helix to reveal the template and nontemplate strands. This “melting” involves

A. Isomerization reaction and it does not require energy derived from ATP hydrolysis

B. Isomerization is essentially irreversible and, once complete, typically guarantees that transcription will subsequently initiate

C. Positions –11 and -2, with respect to the transcription start site.

#Question id: 4122

#Unit 3. Fundamental Processes

RNA Pol uses its active site, in a simple back-reaction, to catalyze the removal of an incorrectly inserted ribonucleotide. This phenomenon known as

#Question id: 4349

#Unit 3. Fundamental Processes

RNA Pol IV and Pol V

#Question id: 4350

#Unit 3. Fundamental Processes

Portions of the DNA sequences of normal and mutant b-globin genes are shown. The most plausible explanation for why the indicated mutation (changing an A to a G) results in the disease b-thalassemia is that the mutation

#Question id: 24464

#Unit 3. Fundamental Processes

#Question id: 24465

#Unit 3. Fundamental Processes

Which of the following is incorrectly matched