How does the Calvin cycle (light-independent reactions) differ from the light-dependent reactions?

Question

Responses

The Calvin cycle is the first step in photosynthesis.
The Calvin cycle is the first step in photosynthesis.

The Calvin cycle requires light energy.
The Calvin cycle requires light energy.

The Calvin cycle produces ATP and NADPH.
The Calvin cycle produces ATP and NADPH.

The Calvin cycle takes place in the stroma.

Answer 1

The differences between the Calvin cycle (light-independent reactions) and the light-dependent reactions of photosynthesis can be summarized as follows:

1. Location: The Calvin cycle takes place in the stroma of the chloroplasts, whereas light-dependent reactions occur in the thylakoid membranes.

2. Light Requirement: The Calvin cycle does not directly require light energy to occur; it can take place in the dark (hence "light-independent"). In contrast, light-dependent reactions require light energy to produce ATP and NADPH.

3. Products: The light-dependent reactions produce ATP and NADPH, which are then used as energy sources in the Calvin cycle. The Calvin cycle, on the other hand, utilizes these products to fix carbon dioxide into organic carbohydrates.

So, the correct response that highlights a key difference is: The Calvin cycle takes place in the stroma.