Question

During a class lecture students were taught about the process of photosynthesis which occurs in the chloroplast. They were told that there are two phases of photosynthesis i.e. light reaction and dark reaction.
Select the correct statements with respect to light reaction.

• A. Light energy is converted into chemical energy and stored in the form of ATP.
• B. CO₂ is reduced to starch, utilising the energy released during this process.
• C. It occurs in the grana of chloroplast in the presence of sunlight.
• D. Water is decomposed into its basic constituents i.e hydrogen and hydroxyl ion.

Answer 1

Answer: (A), (C), (D)

The correct options are
A Light energy is converted into chemical energy and stored in the form of ATP.
C It occurs in the grana of chloroplast in the presence of sunlight.
D Water is decomposed into its basic constituents i.e hydrogen and hydroxyl ion.

Light reaction is also known as light dependent reaction as it can occur only in the presence of light.
It occurs in the grana of the chloroplast where light energy is converted into chemical energy.
Oxygen released during the process of photosynthesis is the result of the decomposition of water into hydrogen and hydroxyl ions.
Whereas CO₂ is reduced into starch in the dark phase by using energy produced during light reaction.