Which of the following is the second major stage of photosynthesis that involves the incorporation of atmospheric CO\(_2\) into organic molecules?

• A. Glycolysis
• B. Calvin cycle
• C. Electron transport chain
• D. Light reactions

Answer: (B)

Verified step by step guidance

1. Understand that photosynthesis occurs in two major stages: the light reactions and the Calvin cycle. The light reactions capture energy from sunlight to produce ATP and NADPH, which are used in the next stage.
2. Recognize that the Calvin cycle is the second major stage of photosynthesis, where atmospheric CO\(_2\) is incorporated into organic molecules through a process called carbon fixation.
3. Recall that the Calvin cycle occurs in the stroma of the chloroplast and does not require light directly, unlike the light reactions.
4. Eliminate the incorrect options: Glycolysis is part of cellular respiration, not photosynthesis; the electron transport chain is part of both cellular respiration and the light reactions, but it is not the second stage of photosynthesis.
5. Conclude that the correct answer is the Calvin cycle, as it is the stage responsible for incorporating CO\(_2\) into organic molecules.