Problem 2
Explain why (a) the flow of energy through the biosphere depends on the cycling of nutrients, and (b) the cycling of nutrients depends on gravity (Concept 3-1B).
Problem 3
Explain why microbes are so important. List two beneficial and two harmful effects of microbes on your health and lifestyle. Write a brief description of what you think would happen to you if microbes were eliminated from the earth.
Problem 4
Make a list of the food you ate for lunch or dinner today. Trace each type of food back to a particular producer species. Describe the sequence of feeding levels that led to your feeding.
Problem 6
Why do farmers not need to apply carbon to grow their crops but often need to add fertilizer containing nitrogen and phosphorus?
Problem 7
What changes might take place in the hydrologic cycle if the earth's climate becomes (a) hotter or (b) cooler? In each case, what are two ways in which these changes might affect your lifestyle?
Problem 8
What would happen to an ecosystem if (a) all its decomposers and detritus feeders were eliminated, (b) all its producers were eliminated, or (c) all its insects were eliminated? Could a balanced ecosystem exist with only producers and decomposers and no consumers such as humans and other animals? Explain.
Problem 10
List two questions that you would like to have answered as a result of reading this chapter.
