BLY 122 CH 25

If a forester treats his soil with a broad-spectrum fungicide, how would this affect the rate of CO2 released from the system? 1. CO2 released from the system will decrease because this would decrease the number of decomposers in the system. 2. CO2 released from the system will increase because the fungi will be decomposed by something else. 3. CO2 released from the system will remain the same because fungi only decompose dead organisms and the forest is alive.

1

Photosynthesis _____ the atmosphere, whereas respiration _____ the atmosphere. 1 removes CO2 from; introduces CO2 to 2 introduces CO2 to; removes CO2 from

1

Photosynthesis and respiration affect atmospheric CO2 levels on a _____ timescale, whereas volcanic eruptions affect atmospheric CO2 levels on a _____ timescale. 1 yearly; century 2 century; yearly

1

Photosynthesis and respiration both play a major role in the _____ carbon cycle, and can affect atmospheric CO2 levels on a seasonal or annual basis. 1 short-term 2 long-term 3 None of the answer options is correct.

1

Recall that in the northern hemisphere, atmospheric CO2 levels are highest in early spring and lowest in early fall. What accounts for this seasonal fluctuation in atmospheric CO2 levels? 1 photosynthesis 2 human activities 3 respiration 4 biomineralization 5 plate tectonics

1

The rate of respiration _____ throughout the year. 1 remains more or less constant 2 varies significantly

1

Which of the following processes is responsible for the changes scientists observed in atmospheric concentrations of 12C, 13C, and 14C over the last 200 years? 1 the burning of fossil fuels 2 volcanism 3 the clearing of forests 4 chemical weathering 5 subduction

1

Which of the following represents an accurate description of the movement of carbon through a food web? 1. Carbon is removed by the producers, and added by the consumers. 2. Carbon is being added to the atmosphere at each level. 3. Carbon is being removed from the atmosphere at each level.

1

Which of the following statements is TRUE about photosynthesis and chemical weathering? 1. Both processes use CO2 as a reactant (i.e., decrease atmospheric CO2 levels). 2. Both processes release CO2 as a product (i.e., increase atmospheric CO2 levels). 3. Both processes are typically associated with the long-term carbon cycle. 4. Both processes are typically associated with the short-term carbon cycle.

1

What can Antarctic ice core samples tell us about atmospheric CO2 levels? (Select all that apply.) 1. Ice cores can help scientists estimate atmospheric CO2 levels from centuries ago. 2. Nothing, because ice is made of H2O and not CO2. 3. CO2 ice core data confirm CO2 measurements taken directly from the atmosphere. 4. Ice cores can tell scientists exactly what plants lived on Earth centuries ago.

1 and 3

Over the last several decades, what have researchers discovered about atmospheric CO2 levels? 1 They have decreased. 2 They have increased. 3 They have remained the same. 4 They increased for a period, but have now stabilized.

2

The _____ cycle deals with geological processes and carbon reservoirs, some of which have been built up (or take place) over a period of millennia. In contrast, the _____ cycle involves biological processes that are carried out on a daily and/or seasonal basis. 1 short-term carbon; long-term carbon 2 long-term carbon; short-term carbon 3 short-term carbon; rapid carbon 4 long-term carbon; intermediate carbon

2

There is evidence that increased levels of CO2 in the atmosphere may increase Earth's surface temperature. How might this affect the spread of mosquitoes and malaria? (Select all that apply.) 1. Warmer temperatures will kill off mosquitoes, thereby decreasing malaria cases. 2. Warmer temperatures may increase the habitat range of mosquitoes. 3. Warmer temperatures will have no affect on mosquitoes or the incidence of malaria. 4. Warmer temperatures may result in malaria cases in new regions.

2 and 4

Which of the following processes INCREASES the amount of CO2 in the atmosphere? (Select all that apply.) 1 photosynthesis 2 volcanic eruptions 3 subduction 4 chemical weathering 5 respiration

2 and 5

Which of the following equations is the chemical reaction for cellular respiration? 1. 6CO2 + 6H2O → C6H12O6 +6O2 2. CaSiO3 +CO2 → CaCO3 +SiO2 3. C6H12O6 + 6O2 → 6CO2 + 6H2O 4. C6H12O6 + 6CO2 → 6O2 + 6H2O

3

Recall that sedimentary rocks, living organisms, oceans, and soil are all carbon reservoirs. If the carbon in each of these reservoirs was instantly transformed into atmospheric CO2, which reservoir would contribute the MOST CO2 to the atmosphere? living organisms soil oceans sedimentary rocks

sedimentary rocks