LG 10 Carbon Cycle

The process of respiration is essential in the oxygen/carbon dioxide cycle. Respiration removes ______ from the atmosphere and produces and releases ______ to the

atmosphere.

• oxygen, carbon dioxide

• carbon dioxide, oxygen

• oxygen, glucose

• glucose, oxygen

Theory states that the extraterrestrial forces that have influenced climate rhythms over the last two million years have occurred primarily because of cyclical changes in Earth’s orbit around the Sun. Identify which statement is true.

• Every 100,000 years, the eccentricity of Earth’s orbit around the Sun oscillates between 5% and 15%.

• Every 100,000 years, the eccentricity of Earth’s orbit around the Sun oscillates between 15% and 30%.

• Every 100,000 years, the eccentricity of Earth’s orbit around the Sun oscillates between 0% and 5%.

• Every 100,000 years, the eccentricity of Earth’s orbit around the Sun oscillates between 0% and 1%.

The process of photosynthesis is essential in the oxygen/carbon dioxide cycle. Photosynthesis removes ______ from the atmosphere and produces and releases ______

into the atmosphere.

• oxygen, carbon dioxide

• carbon dioxide, oxygen

• oxygen, glucose

• glucose, oxygen

Consider the following situations. Throughout the world, scientists have noted that glaciers are (1) melting, (2) calving, and (3) not reforming to any extent. Additionally, the polar ice caps are shrinking. What effect would these occurrences have on the human population?

• The change in ice throughout the world would greatly impact the weather, possibly causing distress to the human population on Earth.

• A decrease in polar ice would cause a decrease in ocean water temperature and that would impact the global climate.

• The melting ice would cause a rise in sea level. That in turn, would cause coastal areas, some heavily populated to be flooded with sea water.

• None, since the human population does not live in the areas mentioned: glaciers and polar ice caps.

CO2 is returned to the atmosphere by all methods EXCEPT

• combustion

• photosynthesis

• decomposition

• respiration

There are many positive feedback loops that accelerate global warming and cause climate change. For example, as polar ice melts due to global warming, there will be __________ sunlight reflected away and consequently, _______________________.

• more, surface temperatures will decrease

• more, surface temperatures will increase

• less, surface temperatures will decrease

• less, surface temperatures will increase

Carbon is a major component of all organic compounds, including carbohydrates, lipids, proteins, and nucleic acids. Carbon dioxide is continually exchanged between the atmosphere and oceans. What geological process returns carbon to the atmosphere in the form of carbon dioxide?

• transpiration

• respiration

• decomposition of marine sediments

• volcanic activity

Which of these would best help with global climate change?

• find and use alternate sources of energy

• stricter standards on water quality

• increase the use of fossil fuels

• decrease the average MPG of our cars

In the carbon cycle, carbon is transferred from animals to decomposers in all of the following ways EXCEPT

• in dead carcasses.

• as waste.

• as carbon dioxide.

• in scraps of discarded food.

Scientists previously referred to the long-ago deposited plant and animal remains, now buried, compacted, and transformed into coal and oil, as the dead-end of the carbon cycle. Since the Industrial Revolution, that would be an inaccurate statement. Why?

• The carbon stored in the coal and oil combines with water in the atmosphere and falls back to Earth.

• the carbon found in coal and oil is released back into the atmosphere as carbon dioxide.

• Factories burning coal and oil deposit industrial wastes that add carbon back into the environment.

• The combustion of coal and oil releases nitrogen by-products into the environment to be used again by man.