Academic Integrity: tutoring, explanations, and feedback — we don’t complete graded work or submit on a student’s behalf.

At times in the geologic past when much organic carbon has been buried, ________

ID: 290709 • Letter: A

Question

At times in the geologic past when much organic carbon has been buried, ____________.

the relative abundance of heavier carbon 12 has increased in the atmosphere and ocean

the relative abundance of lighter carbon 12 has increased in the atmosphere and ocean

the relative abundance of heavier carbon 13 has decreased in the atmosphere and ocean

the relative abundance of heavier carbon 13 has increased in the atmosphere and ocean

Weathering of minerals affects atmospheric CO2 ____________.

by removing CO2 from the atmosphere and depleting the atmospheric reservoir

by increasing CO2 in the atmosphere and increasing the atmospheric reservoir

by removing CO2 from the atmosphere and increasing the atmospheric reservoir

by increasing CO2 in the atmosphere and depleting the atmospheric reservoir of O2

the relative abundance of heavier carbon 12 has increased in the atmosphere and ocean

the relative abundance of lighter carbon 12 has increased in the atmosphere and ocean

the relative abundance of heavier carbon 13 has decreased in the atmosphere and ocean

the relative abundance of heavier carbon 13 has increased in the atmosphere and ocean

Explanation / Answer

the relative abundance of heavier carbon 13 has increased in the atmosphere and ocean. This increase of heavier carbon is indicated in the carbon isotope composition of limestone and of sedimentary organic matter produced by photosynthesis.

by removing CO2 from the atmosphere and depleting the atmospheric reservoir. Weathering of minerals removes CO2 from the atmosphere, and deplete the atmospheric reservoir of CO2. These factors include mountain building, warm climates, high rates of precipitation, and deeply rooted vegetation.