Question 1

Which of the following statements is TRUE regarding CO₂?

Accepted Answer

CO₂ is a coded representation for CO2, which is carbon dioxide. Carbon dioxide is a greenhouse gas, plays a crucial role in Earth's temperature regulation, is produced during respiration, and can be emitted through both natural processes (like volcanic eruptions and respiration) and human activities (such as burning fossil fuels).

Question 2

Which of the following is considered a carbon reservoir?

Accepted Answer

The answer of Which of the following is considered a...

Question 3

Recall that over the last 400,000 years, atmospheric CO₂ levels have fluctuated, with the lowest levels occurring during glacial periods and the highest levels occurring during interglacial periods. Why might atmospheric CO₂ levels be lower during glacial periods?

Accepted Answer

During glacial periods, more carbon is stored in ocean reservoirs because cooler temperatures cause increased oceanic mixing and upwelling, bringing carbon-rich deep water to the surface where it can be absorbed by phytoplankton and other organisms. This results in lower atmospheric CO2 levels.

Question 4

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

The ratio given seems to indicate different isotopes of carbon, which differ in the number of neutrons in the nucleus. Therefore, the scientist most likely differentiated between these forms of carbon by the number of neutrons in each isotope.

Question 5

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

Accepted Answer

Volcanic activity provides minerals and nutrients to land masses through volcanic ash and lava, which aid in weathering processes. Without volcanic activity, weathering rates would decrease and ultimately impact soil fertility and ecosystem productivity. However, the shut down of volcanoes would not directly impact global temperature or atmospheric CO2 levels.

Question 6

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

This is the process of the long-term carbon cycle, which involves the movement of carbon from the atmosphere to sedimentary rocks, to the ocean, and eventually to fossil fuels and long-lasting mineral deposits like limestone.

Question 7

Charles Keeling's work demonstrated that, over the last five decades, atmospheric CO₂ levels have increased.

Accepted Answer

Charles Keeling's work involved measuring atmospheric CO2 levels and his famous "Keeling Curve" showed a clear upward trend in CO2 concentrations over time.

Question 8

Nearly 150 years ago, man-made CO₂ was introduced into the atmosphere primarily through _____. Currently, _____ is the main contributing factor to increased levels of human-produced CO₂ in the atmosphere.

Accepted Answer

According to scientific research, man-made CO₂ was introduced into the atmosphere primarily through deforestation almost 150 years ago. Currently, deforestation remains one of the major contributing factors to increased levels of human-produced CO₂ in the atmosphere. In addition to deforestation, the burning of fossil fuels also contributes significantly to increased levels of human-produced CO₂ in the atmosphere. However, as per the question, deforestation is a more significant factor currently contributing to the increased levels of human-produced CO₂ in the atmosphere.

Question 9

How has Earth's atmosphere been influenced by the fact that, as part of the carbon cycle, some amount of organic carbon is stored in sedimentary rocks and is not immediately re-introduced back into the atmosphere?

Accepted Answer

The storing of organic carbon in sedimentary rocks allowed for oxygen to become a main component of Earth's atmosphere. This occurred because as organic carbon was removed from the atmosphere, photosynthesis was able to produce more oxygen, leading to the buildup of oxygen in Earth's atmosphere. This eventually led to the development of oxygen-breathing organisms.

Question 10

Of the processes that release CO₂ to the atmosphere, which are influenced by human technology?

Accepted Answer

Burning of organic carbon that has been stored in sediments and sedimentary rocks, such as coal and oil, is a human technological process that releases CO₂ to the atmosphere through combustion of fossil fuels for energy.

Question 11

CO₂ is an example of a _____, a gas in the atmosphere that is transparent to solar radiation but can absorb heat emitted from Earth's surface.

Accepted Answer

CO₂ is a chemical formula for carbonyl sulfide, which is a greenhouse gas that absorbs heat emitted from Earth's surface.

Question 12

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

Accepted Answer

Volcanoes are a major source of sulfur dioxide (SO2) emissions, which react with water vapor in the atmosphere to form sulfuric acid (H2SO4) aerosols. These aerosols contribute to the formation of clouds and help to cool the planet by reflecting incoming solar radiation back into space. Therefore, if Earth's volcanoes were to all shut down, there would be a decrease in SO2 emissions and a subsequent reduction in the formation of sulfuric acid aerosols. This would lead to a slow decrease in atmospheric CO2 levels and a warming of the planet.

Question 13

Which of the following processes are typically associated with the long-term carbon cycle?

Accepted Answer

The long-term carbon cycle involves processes that store carbon for millions of years, such as the burial of carbon in sediments and volcanic eruptions, which release carbon back into the atmosphere.

Question 14

Which of the processes listed below naturally release CO₂ into the atmosphere?

Accepted Answer

The answer of Which of the processes listed below naturally...

Question 15

How is atmospheric oxygen linked to the carbon cycle?

Accepted Answer

The answer of How is atmospheric oxygen linked to the...

Question 16

Seasonal respiration rates fluctuate in a similar manner as seasonal photosynthesis rates.

Accepted Answer

The answer of Seasonal respiration rates fluctuate in a similar...

Question 17

A researcher is comparing atmospheric CO₂ levels in Earth's northern and southern hemispheres during June and August. Since more terrestrial plants are present in the northern hemisphere, what do you expect she will find?

Accepted Answer

The answer of A researcher is comparing atmospheric CO₂ levels...

Question 18

Over the last 400,000 years, how have atmospheric CO₂ levels changed?

Accepted Answer

Based on the data from ice cores, atmospheric CO2 levels have fluctuated over the last 400,000 years, with periods of higher and lower concentrations. However, it's important to note that the current rate of increase is much faster than any natural fluctuations seen in the past.

Question 19

Which of the following statements is TRUE about photosynthesis and chemical weathering?

Accepted Answer

Both photosynthesis and chemical weathering use CO2 as a reactant, thereby decreasing atmospheric CO2 levels.

Question 20

The observation that atmospheric CO₂levels were typically low during glacial periods in Earth's history is an example of:

Accepted Answer

The observation shows a correlation between atmospheric COS levels and glacial periods, meaning that they are associated with each other but not necessarily causal.

Quiz 25: Cycling Carbon

Which of the following statements is TRUE regarding CO₂?

Which of the following is considered a carbon reservoir?

Recall that over the last 400,000 years, atmospheric CO₂ levels have fluctuated, with the lowest levels occurring during glacial periods and the highest levels occurring during interglacial periods. Why might atmospheric CO₂ levels be lower during glacial periods?

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?

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

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.

Charles Keeling's work demonstrated that, over the last five decades, atmospheric CO₂ levels have increased.

Nearly 150 years ago, man-made CO₂ was introduced into the atmosphere primarily through _. Currently, _ is the main contributing factor to increased levels of human-produced CO₂ in the atmosphere.

How has Earth's atmosphere been influenced by the fact that, as part of the carbon cycle, some amount of organic carbon is stored in sedimentary rocks and is not immediately re-introduced back into the atmosphere?

Of the processes that release CO₂ to the atmosphere, which are influenced by human technology?

CO₂ is an example of a _____, a gas in the atmosphere that is transparent to solar radiation but can absorb heat emitted from Earth's surface.

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

Which of the following processes are typically associated with the long-term carbon cycle?

Which of the processes listed below naturally release CO₂ into the atmosphere?

How is atmospheric oxygen linked to the carbon cycle?

Seasonal respiration rates fluctuate in a similar manner as seasonal photosynthesis rates.

A researcher is comparing atmospheric CO₂ levels in Earth's northern and southern hemispheres during June and August. Since more terrestrial plants are present in the northern hemisphere, what do you expect she will find?

Over the last 400,000 years, how have atmospheric CO₂ levels changed?

Which of the following statements is TRUE about photosynthesis and chemical weathering?

The observation that atmospheric CO₂levels were typically low during glacial periods in Earth's history is an example of:

Quiz 25: Cycling Carbon

Which of the following statements is TRUE regarding CO2?

Which of the following is considered a carbon reservoir?

Recall that over the last 400,000 years, atmospheric CO2 levels have fluctuated, with the lowest levels occurring during glacial periods and the highest levels occurring during interglacial periods. Why might atmospheric CO2 levels be lower during glacial periods?

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?

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

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.

Charles Keeling's work demonstrated that, over the last five decades, atmospheric CO2 levels have increased.

Nearly 150 years ago, man-made CO2 was introduced into the atmosphere primarily through _____. Currently, _____ is the main contributing factor to increased levels of human-produced CO2 in the atmosphere.

How has Earth's atmosphere been influenced by the fact that, as part of the carbon cycle, some amount of organic carbon is stored in sedimentary rocks and is not immediately re-introduced back into the atmosphere?

Of the processes that release CO2 to the atmosphere, which are influenced by human technology?

CO2 is an example of a _____, a gas in the atmosphere that is transparent to solar radiation but can absorb heat emitted from Earth's surface.

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

Which of the following processes are typically associated with the long-term carbon cycle?

Which of the processes listed below naturally release CO2 into the atmosphere?

How is atmospheric oxygen linked to the carbon cycle?

Seasonal respiration rates fluctuate in a similar manner as seasonal photosynthesis rates.

A researcher is comparing atmospheric CO2 levels in Earth's northern and southern hemispheres during June and August. Since more terrestrial plants are present in the northern hemisphere, what do you expect she will find?

Over the last 400,000 years, how have atmospheric CO2 levels changed?

Which of the following statements is TRUE about photosynthesis and chemical weathering?

The observation that atmospheric CO2 levels were typically low during glacial periods in Earth's history is an example of:

Which of the following statements is TRUE regarding CO₂?

Recall that over the last 400,000 years, atmospheric CO₂ levels have fluctuated, with the lowest levels occurring during glacial periods and the highest levels occurring during interglacial periods. Why might atmospheric CO₂ levels be lower during glacial periods?

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?

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.

Charles Keeling's work demonstrated that, over the last five decades, atmospheric CO₂ levels have increased.

Nearly 150 years ago, man-made CO₂ was introduced into the atmosphere primarily through _. Currently, _ is the main contributing factor to increased levels of human-produced CO₂ in the atmosphere.

Of the processes that release CO₂ to the atmosphere, which are influenced by human technology?

CO₂ is an example of a _____, a gas in the atmosphere that is transparent to solar radiation but can absorb heat emitted from Earth's surface.

Which of the processes listed below naturally release CO₂ into the atmosphere?

A researcher is comparing atmospheric CO₂ levels in Earth's northern and southern hemispheres during June and August. Since more terrestrial plants are present in the northern hemisphere, what do you expect she will find?

Over the last 400,000 years, how have atmospheric CO₂ levels changed?

The observation that atmospheric CO₂levels were typically low during glacial periods in Earth's history is an example of: