Explain the light reaction of photosynthesis.

Solution:


The process of photosynthesis occurs in two phases – the light reactions and the dark reactions.

Light reactions – As the name suggests, this reaction takes place in the presence of light. Light energy is absorbed by chlorophyll molecules and is utilized for splitting water molecules into hydrogen and oxygen. Additionally in this phase, assimilatory power in the form of ATP and NADPH₂ are produced.

Light reactions occur in the membranes of thylakoids.

Events occurring during light reactions:

• Absorption of light energy by chlorophyll molecules

• Splitting of water molecules into hydrogen and oxygen atoms

• Formation of ATP and NADPH₂