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The population profile depicted below is based on actual data from a country. Based on the population information contained in the profile, what can you tell about this country?   

What is the final community of organisms to predominate during ecological succession?

Deep in the ocean are communities nestled around hydrothermal vents where super-heated water springs from the bottom of the ocean.  No sunlight ever penetrates to these deep regions. The water from the vents is rich in dissolved minerals such as hydrogen sulfide which supports a large population of chemoautotrophic bacteria that use sulfur compounds to form organic matter by chemosynthesis.  These communities frequently have worms, clams, shrimp, and many other organisms clustered together. In hydrothermal vent communities, we would not expect to find ___.

By destroying habitats, human activity can act like a forest fire or other random disturbance. This kind of disturbance acts as a ___.

Animals that feed on dead organic matter in the soil (such as earthworms, millipedes, and termites) are ___. 

The observation that some usable energy is lost in every energy conversion is explained by the ___. 

The combination of all the abiotic and biotic factors that limit population increase is called ___.

Researchers wanted to determine if pesticide X was effective at killing grasshoppers that typically invade cornfields. Two ten-acre cornfields located 1 mile apart were chosen. The cornfield to the west was sprayed only with water. The cornfield on the east received the same amount of water with a 10% solution of pesticide X. Grasshopper abundance was measured in the fields every week for 10 weeks.  The results were: West field – the number of grasshoppers doubled East field – the number of grasshoppers declined by 50% Based on the results given, what is the most accurate conclusion you can make?

At what stage of the demographic transition is population growth rate at its greatest?   

In fatty acid β-oxidation, the first catalyzed step is given below. This reaction is most similar to what other reaction that we have studied?