Question

Given below are two statements
Statement I: Photosynthesis is a reduction process whereas respiration is an oxidation process
Statement II: Photosynthesis process is not sensitive to the wavelength of light
In the light of the above statements, choose the most appropriate 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 correct but Statement II is false
• D. Statement I is incorrect but Statement II is true

Hint:

Photosynthesis = Anabolic, Reductive, Endergonic.
Respiration = Catabolic, Oxidative, Exergonic.

Answer 1

The Correct Option is C

Step 1: Understanding the Concept:
Bioenergetics and plant physiology define photosynthesis as an endergonic reductive process and respiration as an exergonic oxidative process.
Key Formula or Approach:
\[ 6\text{CO}_2 + 12\text{H}_2\text{O} \xrightarrow{h\nu, \text{Chlorophyll}} \text{C}_6\text{H}_{12}\text{O}_6 + 6\text{O}_2 + 6\text{H}_2\text{O} \quad \text{(Reductive)} \]
\[ \text{C}_6\text{H}_{12}\text{O}_6 + 6\text{O}_2 \longrightarrow 6\text{CO}_2 + 6\text{H}_2\text{O} + \text{Energy} \quad \text{(Oxidative)} \]

Step 2: Detailed Explanation:
1. Statement I: In photosynthesis, carbon dioxide ($\text{CO}_2$) is reduced to glucose while water is oxidized. In respiration, organic carbon (glucose) is oxidized to $\text{CO}_2$. Hence, Statement I is correct.
2. Statement II: Photosynthesis is highly sensitive to the wavelength of incident light. It operates within the Photosynthetically Active Radiation (PAR) band (400--700 nm), exhibiting maximum absorption and quantum yield in the blue (430--470 nm) and red (650--680 nm) spectra. Hence, Statement II is false.

Step 3: Final Answer:
Therefore, Statement I is correct but Statement II is false, matching option (C).