Question

Given below are two statements:
Statement (I): The Calvin cycle, also known as the light-independent reactions of photosynthesis, occurs in the stroma of the chloroplast.
Statement (II): The products of photosynthesis are carbon dioxide and water only.
In light of the above statements, choose the most appropriate answer from the options given below:

• A. Both Statement (I) and Statement (II) are true.
• B. Both Statement (I) and Statement (II) are false.
• C. Statement (I) is true but Statement (II) is false.
• D. Statement (I) is false but Statement (II) is true.

Hint:

Remember the basic photosynthesis equation: plants consume carbon dioxide and water to produce sugars (energy) and oxygen (byproduct).

Answer 1

The Correct Option is C

Step 1: Understanding the Concept:
Photosynthesis is the biochemical process by which plants, algae, and some bacteria convert light energy into chemical energy.
It consists of two main stages: the light-dependent reactions (which capture light energy) and the light-independent reactions (or Calvin cycle, which fix carbon dioxide into sugars).

Step 2: Detailed Explanation:
Let us evaluate both statements:
- Statement (I) is true: The Calvin cycle does not directly require light and occurs in the stroma, the fluid-filled space surrounding the thylakoid membranes inside the chloroplast.
The stroma contains the necessary soluble enzymes, such as RuBisCO, to perform carbon fixation.
- Statement (II) is false: The chemical equation for photosynthesis is:
\[ 6\text{CO}_2 + 6\text{H}_2\text{O} + \text{light energy} \rightarrow \text{C}_6\text{H}_{12}\text{O}_6 + 6\text{O}_2 \] This shows that carbon dioxide (\(\text{CO}_2\)) and water (\(\text{H}_2\text{O}\)) are the reactants of photosynthesis, not the products.
The primary products of photosynthesis are glucose (sugars) and molecular oxygen (\(\text{O}_2\)).
Therefore, Statement (I) is true, but Statement (II) is false.

Step 3: Final Answer:
Hence, the correct option is (C).