Chapter 42

In most ecosystems, the primary producers use energy from ____________ to build organic compounds. a. sunlight b. heat c. breakdown of wastes and remains d. breakdown of inorganic substances in the habitat

Organisms at the lowest trophic level in a tallgrass prairie are all ______________ . a. at the first step away from the original energy input b. autotrophs c. heterotrophs d. both a and b e. both a and \(c\)

Decomposers are commonly __________ . a. fungi b. plants c. bacteria d. a and \(c\)

All organisms at the first trophic level _____________ . a. capture energy from a nonliving source b. are eaten by organisms at higher trophic levels c. would be at the bottom of an energy pyramid d. all of the above

Primary productivity on land is affected by _____________ . a. nutrient availability b. amount of sunlight c. temperature d. all of the above

If biological magnification occurs, the ____________ will have the highest levels of toxins in their systems. a. producers b. herbivores c. primary carnivores d. top carnivores

Earth's largest carbon reservoir is _____________ a. the atmosphere b. sediments and rocks c. seawater d. living organisms

Carbon is released into the atmosphere by _________ . a. photosynthesis b. aerobic respiration c. burning fossil fuels d. \(b\) and \(c\)

Greenhouse gases ___________. a. slow escape of heat energy from Earth into space b. are produced by natural and human activities c. are at higher levels than they were 100 years ago d. all of the above

The ___________ cycle is a sedimentary cycle. a. hydrologic b. carbon c. sediments and rocks d. living organisms

Earth's largest phosphorus reservoir is ___________ . a. the atmosphere b. guano c. sediments and rocks d. living organisms

Plant growth requires _____________ uptake from the soil. a. nitrogen b. carbon c. phosphorus d. both a and c e. all of the above

Nitrogen fixation converts __________ to _____________ . a. nitrogen gas; ammonia b. nitrates; nitrites c. ammonia; nitrogen gas d. ammonia; nitrates e. nitrites; nitrogen oxides

Match each term with its most suitable description. a. feed on plants b. feed on small bits of organic matter c. degrade organic wastes and remains to inorganic forms d. capture sunlight energy producers herbivores decomposers detritivores