Nres219 EXAM QUESTIONS AND ANSWERS

Nres219 EXAM QUESTIONS AND ANSWERS Which of the following statements about change in communities is true? ? ?? Only biotic factors can be agents of change. Only abiotic factors can be agents of change. Disturbances create opportunities for some species to grow and reproduce due to the injury or death of other individuals. "Stress" and "disturbance" are interchangeable words that describe the same process. Humans are the only agents of change for biological communities. - ANSWER Disturbances create opportunities for some species to grow and reproduce due to the injury or death of other individuals. Which of the following human activities can bring about shifts in communities that lead to alternative stable states? habitat destruction introduction of invasive species overexploitation of native species all of the above none of the above - ANSWER all of the above Although beavers are relatively rare, they have considerable influence over species interactions in communities in which they are present, because their dams dramatically alter the environment. The beaver is an example of a(n) __________. ? ?? a. foundation species b. keystone species c. ecosystem engineer? d. Both a and b e. both b and c - ANSWER both b and c What is the primary difference between interaction webs and food webs? Interaction webs include more trophic levels.? Interaction webs include fewer trophic levels. Interaction webs do not consider primary producers, whereas food webs do. Interaction webs include non-trophic interactions, whereas food webs do not. There is no difference between food webs and interaction webs. ? ?? - ANSWER Interaction webs include non-trophic interactions, whereas food webs do not. Cougars prey on both white-tailed deer and mule deer. Because of their shared predator, each of deer species' abundance is affected by the presence of the other deer species. In this situation, the white-tailed deer and mule deer are engaged in a direct interaction.? an indirect interaction. a trophic facilitation. a Shannon interaction. a "Red Queen" arms race. - ANSWER an indirect interaction Which of the following can be measured the most easily? Species evenness Species richness Species diversity Species evenness and richness are equally easy to measure.? These are all theoretical concepts that cannot be measured. - ANSWER Species richness According to the __________ model of succession, the early successional species modify the environment so as to make it better for later successional species. facilitation tolerance inhibition Cowles