History of Earth's Atmosphere II | Earth Science | Quiz

What chemical is the source of the oxygen produced in photosynthesis?

Air

Carbon dioxide

Water

Iron oxide
When William Schopf first discovered microfossils, he was able to show that ______ is/are older than 600 million years.

land plants

photosynthetic microorganisms

oxygen gas

banded iron formations
Banded Iron Formations (BIFs) provide evidence that the early Earth lacked oxygen because

they cannot form in the presence of abundant oxygen gas.

they formed as sedimentary rocks in the oceans.

they formed continuously for 1 billion years.

they cannot form without the help of biological organisms.
In addition to Banded Iron Formations (BIFs), which line of evidence helped establish the timing of the Great Oxidation Event?

Life on Earth arose between 3.8 and 3.5 billion years ago.

Land plants evolved about 450 million years ago.

Mars lost its atmosphere more than 4 billion years ago.

Iron-rich “redbeds” began forming on land 2 billion years ago.
Uraninite forms a solid in the presence of oxygen.

true

false
The definition of mass independent fractionation (MIF) is when a reaction occurs and the abundances of different isotopes

follow an expected pattern with more light isotopes and fewer heavy isotopes.

follow an expected pattern with relatively more heavy isotopes than expected.

do not follow an expected pattern. Rather, the pattern cannot be predicted from their mass.

are equal.
Given a sulfur sample with the following relative abundances of sulfur isotopes (shown as δ^3XS), which of the following is NOT an example of mass independent fractionation?

δ³⁴S > δ³³S > δ³²S > δ³⁶S

δ³⁶S > δ³³S > δ³⁴S >δ³²S

δ³²S> δ³³S> δ³⁴S> δ³⁶S

δ³²S > δ³⁶S > δ³³S > δ³⁴S