Astronomy quiz question: carbon dioxide sink

Astronomy 210 Quiz 7, Spring Semester 2011
Cuesta College, San Luis Obispo, CA

Where does the carbon dioxide in Earth's atmosphere go before it is recycled back down into the mantle?
(A) Volcanoes.
(B) Plants.
(C) Oceans.
(D) Polar ice caps.

Correct answer: (C)

Oceans absorb vast amounts of carbon dioxide, which settle into sedimentary rocks on ocean floors, which are then subsequently subducted back into the mantle.

Section 30674
Exam code: quiz07N3mi
(A) : 4 students
(B) : 6 students
(C) : 26 students
(D) : 0 students

"Success level": 74% (including partial credit for multiple-choice)
Discrimination index (Aubrecht & Aubrecht, 1983): 0.50

Section 30676
Exam code: quiz07Sq5h
(A) : 3 students
(B) : 12 students
(C) : 22 students
(D) : 3 students

"Success level": 59% (including partial credit for multiple-choice)
Discrimination index (Aubrecht & Aubrecht, 1983): 0.82

Compare to a similar version of this question from Fall 2009.