119.Of the following carbon-based compounds, which would have the slowest turnover rate?
120.The two ways in which humans have most interfered with the carbon cycle are
121.Computer models suggest that adding carbon dioxide to the atmosphere could
122.The nitrogen cycle is considered to be a A.gaseous cycle.B. sedimentary cycle.C. hydrologic cycle.D. double cycle.E. rock cycle.
123.The mostcommon gas in the atmosphere is
124.Nitrogen is a major component of all of the following except
125.Nodules containing nitrogen-fixing bacteria would be expected to occur on the roots of
126.Nitrogen fixation is accomplished by A. earthworms.B.cyanobacteria.C. algae.D. protozoa.E. legumes.