Question 1

Why are carbon-based organic compounds, such as C6H12O6 (glucose) , often referred to as "energy molecules"?

Accepted Answer

A)  Energy is released when carbon-containing compounds are broken down.
B)  Energy is stored in carbon-containing organic compounds.
C)  Energy is required to build carbon-containing organic compounds.
D)  None of the answer options is correct.

Question 2

The CO2 level is _____ during winter in the northern hemisphere compared to levels in the summer.

Accepted Answer

A)  lower
B)  higher
C)  the same

Question 3

The levels of CO2 in the atmosphere have been:

Accepted Answer

A)  increasing.
B)  decreasing.
C)  staying the same.

Question 4

How is atmospheric oxygen linked to the carbon cycle?

Accepted Answer

A)  More burial of organic carbon in sediments results in more oxygen in the atmosphere and oceans.
B)  More photosynthesis leads to more oxygen in the atmosphere and oceans.
C)  More volcanic CO2 emission leads to more oxygen in the atmosphere and oceans.
D)  Longer food chains with more consumers lead to more oxygen in the atmosphere and oceans.

Question 5

The evolution of biodiversity on the planet can be linked to patterns in the carbon cycle over time.

Accepted Answer

A) True 
 B)False

Question 6

A botanist is comparing the metabolic pathways for photosynthesis in cyanobacteria and in redwood trees. What do you expect she will find?

Accepted Answer

A)  These two pathways will demonstrate dramatic differences.
B)  These two pathways will utilize two chemically different types of chlorophyll.
C)  These two pathways will actually be quite similar, though subtle differences may exist.
D)  It is impossible to compare metabolic pathways used in bacteria and eukaryotes.

Question 7

Of the processes involved in the long-term carbon cycle, which introduces CO2 back into the atmosphere?

Accepted Answer

A)  chemical weathering
B)  carbonate precipitation
C)  volcanism
D)  respiration
E)  photosynthesis

Question 8

Recall that photosynthetic rates remain relatively constant in regions near the equator. Imagine that tropical environments persisted throughout Earth's northern and southern hemispheres (i.e., Earth's entire climate mirrored that near the equator) . If Keeling had collected his atmospheric CO2 data on such an Earth, what would you expect the Keeling Curve to look like?

Accepted Answer

A)  a straight line sloping upward (atmospheric CO2 levels would not seasonally oscillate, but would have increased over time) 
B)  a straight line sloping downward (atmospheric CO2 levels would not seasonally oscillate, but would have decreased over time) 
C)  a sinusoidal curve sloping upward (atmospheric CO2 levels would fluctuate seasonally, but would increase over time) 
D)  a sinusoidal curve sloping downward (atmospheric CO2 levels would fluctuate seasonally, but would have decreased over time) 
E)  a straight line without a slope (atmospheric CO2 levels would have remained constant over time)

Question 9

The movement of carbon from CO2 in the atmosphere to HCO3-(a byproduct of chemical weathering)  on rocks to CaCO3 in coral skeletons and finally CaCO3 in limestone are all steps in the _____ cycle.

Accepted Answer

A)  short-term carbon
B)  nitrogen
C)  sulfur
D)  long-term carbon

Question 10

Cellular respiration is a process unique to animals, and is not undertaken by plants.

Accepted Answer

A) True 
 B)False

Question 11

The rate of exchange of carbon between the atmosphere and the oceans represents a carbon:

Accepted Answer

A)  sink.
B)  reservoir.
C)  biomass.
D)  precipitation.
E)  flux.

Question 12

_____ describe(s)  the rates at which carbon is transferred from one reservoir to another.

Accepted Answer

A)  Respiration
B)  Sinks
C)  Fluxes
D)  Erosion

Question 13

What would be the environmental consequences if Earth's volcanoes all shut down tomorrow?

Accepted Answer

A)  CO2 levels in the atmosphere would slowly rise.
B)  CO2 levels in the atmosphere would slowly fall.
C)  Rates of continental weathering would slowly increase.
D)  Temperature would slowly increase.

Question 14

When we think about the carbon cycle and human activities, it is important to differentiate between facts and hypotheses. Which of the following can be considered a fact?

Accepted Answer

A)  The amount of carbon dioxide in the atmosphere has increased since 1950.
B)  Increasing atmospheric carbon dioxide will cause mean global temperature to increase by 2 degrees Celsius over the next century.
C)  The burning of fossil fuels contributes substantially to the ongoing rise of atmospheric CO2.
D)  In the past, atmospheric CO2 levels reached levels higher than those observed today.

Question 15

What would be the environmental consequences if Earth's volcanoes all shut down tomorrow?

Accepted Answer

A)  CO2 levels in the atmosphere would slowly rise.
B)  Continental weathering would decrease.
C)  Rates of continental weathering would slowly increase.
D)  Temperature would slowly increase.

Question 16

Which of the following things are made (in part)  of carbon?

Accepted Answer

A)  the shells of clams and other mollusks
B)  the glucose/sugars in fruits
C)  limestone at the bottom of the sea
D)  certain gases in the atmosphere

Question 17

A scientist studying a material has determined that 12C, 13C, and 14C occur in the material in a ratio of 1000:10:1. How did he MOST likely differentiate between these forms of carbon?

Accepted Answer

A)  by the number of protons in 12C, 13C, and 14C
B)  by the number of electrons in 12C, 13C, and 14C
C)  by the number of neutrons in 12C, 13C, and 14C
D)  by the biomasses of 12C, 13C, and 14C
E)  by the number of positrons in 12C, 13C, and 14C

Question 18

Which of the following statements explains how an oxygen-rich atmosphere was possible?

Accepted Answer

A)  The number of plants has always outnumbered the animals.
B)  Photosynthetic organisms have existed on earth longer than heterotrophs.
C)  Rates of carbon fixation and respiration have always been equal.
D)  Rates of oxygen consumption were lower than rates of photosynthesis.
E)  All of these choices are correct.

Question 19

Of the processes involved in the long-term carbon cycle, which removes CO2 from the atmosphere?

Accepted Answer

A)  chemical weathering
B)  volcanism
C)  respiration
D)  photosynthesis
E)  bacteria-based oxidation

Question 20

The diverse array of photosynthetic plants and microbes is the result of different sources of CO2, and has little to do with environmental conditions.

Accepted Answer

A) True 
 B)False

Exam 25: Cycling Carbon

A scientist studying a material has determined that ¹²C, ¹³C, and ¹⁴C occur in the material in a ratio of 1000:10:1. How did he MOST likely differentiate between these forms of carbon?

Correct Answer
verified

The levels of CO₂ in the atmosphere have been:

Correct Answer
verified

Of the processes involved in the long-term carbon cycle, which introduces CO₂ back into the atmosphere?

Correct Answer
verified

Correct Answer
verified

Which of the following things are made (in part) of carbon?

Correct Answer
verified

The CO₂ level is _____ during winter in the northern hemisphere compared to levels in the summer.

Correct Answer
verified

When we think about the carbon cycle and human activities, it is important to differentiate between facts and hypotheses. Which of the following can be considered a fact?

Correct Answer
verified

What would be the environmental consequences if Earth's volcanoes all shut down tomorrow?

Correct Answer
verified

How is atmospheric oxygen linked to the carbon cycle?

Correct Answer
verified

Which of the following statements explains how an oxygen-rich atmosphere was possible?

Correct Answer
verified

The rate of exchange of carbon between the atmosphere and the oceans represents a carbon:

Correct Answer
verified

The diverse array of photosynthetic plants and microbes is the result of different sources of CO₂, and has little to do with environmental conditions.

Correct Answer
verified

What would be the environmental consequences if Earth's volcanoes all shut down tomorrow?

Correct Answer
verified

Of the processes involved in the long-term carbon cycle, which removes CO₂ from the atmosphere?

Correct Answer
verified

The evolution of biodiversity on the planet can be linked to patterns in the carbon cycle over time.

Correct Answer
verified

_____ describe(s) the rates at which carbon is transferred from one reservoir to another.

Correct Answer
verified

A botanist is comparing the metabolic pathways for photosynthesis in cyanobacteria and in redwood trees. What do you expect she will find?

Correct Answer
verified

The movement of carbon from CO₂ in the atmosphere to HCO₃^-(a byproduct of chemical weathering) on rocks to CaCO₃ in coral skeletons and finally CaCO₃ in limestone are all steps in the _____ cycle.

Correct Answer
verified

Why are carbon-based organic compounds, such as C₆H₁₂O₆ (glucose) , often referred to as "energy molecules"?

Correct Answer
verified

Cellular respiration is a process unique to animals, and is not undertaken by plants.

Correct Answer
verified

Exam 25: Cycling Carbon

A scientist studying a material has determined that 12C, 13C, and 14C occur in the material in a ratio of 1000:10:1. How did he MOST likely differentiate between these forms of carbon?

Correct AnswerverifiedShow Answer

The levels of CO2 in the atmosphere have been:

Correct AnswerverifiedShow Answer

Of the processes involved in the long-term carbon cycle, which introduces CO2 back into the atmosphere?

Correct AnswerverifiedShow Answer

Correct AnswerverifiedShow Answer

Which of the following things are made (in part) of carbon?

Correct AnswerverifiedShow Answer

The CO2 level is _____ during winter in the northern hemisphere compared to levels in the summer.

Correct AnswerverifiedShow Answer

When we think about the carbon cycle and human activities, it is important to differentiate between facts and hypotheses. Which of the following can be considered a fact?

Correct AnswerverifiedShow Answer

What would be the environmental consequences if Earth's volcanoes all shut down tomorrow?

Correct AnswerverifiedShow Answer

How is atmospheric oxygen linked to the carbon cycle?

Correct AnswerverifiedShow Answer

Which of the following statements explains how an oxygen-rich atmosphere was possible?

Correct AnswerverifiedShow Answer

The rate of exchange of carbon between the atmosphere and the oceans represents a carbon:

Correct AnswerverifiedShow Answer

The diverse array of photosynthetic plants and microbes is the result of different sources of CO2, and has little to do with environmental conditions.

Correct AnswerverifiedShow Answer

What would be the environmental consequences if Earth's volcanoes all shut down tomorrow?

Correct AnswerverifiedShow Answer

Of the processes involved in the long-term carbon cycle, which removes CO2 from the atmosphere?

Correct AnswerverifiedShow Answer

The evolution of biodiversity on the planet can be linked to patterns in the carbon cycle over time.

Correct AnswerverifiedShow Answer

_____ describe(s) the rates at which carbon is transferred from one reservoir to another.

Correct AnswerverifiedShow Answer

A botanist is comparing the metabolic pathways for photosynthesis in cyanobacteria and in redwood trees. What do you expect she will find?

Correct AnswerverifiedShow Answer

The movement of carbon from CO2 in the atmosphere to HCO3-(a byproduct of chemical weathering) on rocks to CaCO3 in coral skeletons and finally CaCO3 in limestone are all steps in the _____ cycle.

Correct AnswerverifiedShow Answer

Why are carbon-based organic compounds, such as C6H12O6 (glucose) , often referred to as "energy molecules"?

Correct AnswerverifiedShow Answer

Cellular respiration is a process unique to animals, and is not undertaken by plants.

Correct AnswerverifiedShow Answer

A scientist studying a material has determined that ¹²C, ¹³C, and ¹⁴C occur in the material in a ratio of 1000:10:1. How did he MOST likely differentiate between these forms of carbon?

Correct Answer
verified

The levels of CO₂ in the atmosphere have been:

Correct Answer
verified

Of the processes involved in the long-term carbon cycle, which introduces CO₂ back into the atmosphere?

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

The CO₂ level is _____ during winter in the northern hemisphere compared to levels in the summer.

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

The diverse array of photosynthetic plants and microbes is the result of different sources of CO₂, and has little to do with environmental conditions.

Correct Answer
verified

Correct Answer
verified

Of the processes involved in the long-term carbon cycle, which removes CO₂ from the atmosphere?

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

The movement of carbon from CO₂ in the atmosphere to HCO₃^-(a byproduct of chemical weathering) on rocks to CaCO₃ in coral skeletons and finally CaCO₃ in limestone are all steps in the _____ cycle.

Correct Answer
verified

Why are carbon-based organic compounds, such as C₆H₁₂O₆ (glucose) , often referred to as "energy molecules"?

Correct Answer
verified

Correct Answer
verified