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Gram Stain: GPC in chains BAP Morphology: Alpha hemolytic colonies Tests: Catalase negative; ‘P’ disc resistant; BE negative.  Diseases: Endocarditis What is your Presumptive ID?

Gram Stain: GPC in clusters BAP Morphology: Beta hemolytic, golden colonies Tests: Catalase positive; Coagulase positive Diseases: TSS What is your Presumptive ID?

Pick 2 reasons for specimen rejection:

Which type of disturbance is most likely to promote species richness in a forest?

For this feedback loop scenario, fill in the completion of the loop and the type of feedback loop as you did in class examples. Background: Land desertification is a process by which fertile land becomes desert, typically because of hotter and drier conditions. This results in greater amounts of windblown dust entering the atmosphere, which reflects sunlight back into space rather than it reaching the Earth’s surface. Beginning of Loop: Rising atmospheric carbon dioxide concentrations results in longer periods of drought and extreme heat. Completion of loop: Type of feedback loop:  

Background: As global temperatures rise, melting occurs on the surface of polar glaciers. This meltwater trickles down through cracks in the glacier, reaching its base. At the glacier’s base, the water acts as a lubricant between the ice and the bedrock, allowing the glacier to slide. Part A: Explain how the sliding of glaciers into the ocean, driven by this lubrication process, could influence global temperatures. Be sure to describe the mechanism through which this process affects the climate system. Part B: Propose an intervention to slow this glacier sliding process and explain how it would work in terms of modifying the described mechanism.

Which species would make the best candidate for a flagship conservation effort?

This question is to ensure that you are in the room taking the exam. What is the two word passcode for this exam?  

Analyze this dataset on forest recovery after fire: Time Post-Fire (years) Species Richness Productivity 1 5 Low 5 15 Moderate 10 25 High Which hypothesis about the relationship between ecosystem function and species richness does this best support?

In a study led by Dave Tilman at the University of Minnesota, researchers measured a variety of parameters every year in grassland plots that had been planted with different species richnesses.  One year there was a severe drought.  The researchers compared the biomass of plants in the year following the drought to the biomass of the plants in the year preceding the drought and got the following data.  What are reasonable conclusions from these data? Choose “supported” or “not supported” for each statement.   *numbers in graph indicate how many plots had that number of species. Plots with high species richness (compared to those with very low species richness) had greater resistance to the effects of the drought on biomass. [ans2] The drought decreased species richness[ans3] If we assume that the species-rich plots are also higher in diversity, these data support the diversity-stability hypothesis[ans4]