In which part of the chloroplast does the Calvin Cycle occur?

• A. Outer membrane
• B. Stroma
• C. Thylakoid membrane
• D. Granum

Answer: (B)

Verified step by step guidance

1. Understand the structure of the chloroplast: Chloroplasts are organelles found in plant cells and are the site of photosynthesis. They have an outer membrane, an inner membrane, and internal structures called thylakoids, which are stacked into grana. The fluid-filled space surrounding the thylakoids is called the stroma.
2. Identify the location of the Calvin Cycle: The Calvin Cycle, also known as the light-independent reactions or dark reactions, takes place in the stroma of the chloroplast. This is where the enzymes necessary for the Calvin Cycle are located.
3. Differentiate between the thylakoid membrane and the stroma: The thylakoid membrane is where the light-dependent reactions occur, which produce ATP and NADPH. These products are then used in the stroma during the Calvin Cycle to fix carbon dioxide into glucose.
4. Clarify the role of the stroma: The stroma contains the enzymes required for the Calvin Cycle, such as ribulose bisphosphate carboxylase/oxygenase (RuBisCO), which catalyzes the first step of carbon fixation.
5. Summarize the process: In the stroma, ATP and NADPH produced in the thylakoid membrane are used to convert carbon dioxide into glucose through a series of reactions known as the Calvin Cycle.