During which stage of photosynthesis is light energy converted to chemical energy?

The correct choice involves the light-dependent reactions, which are a crucial phase of photosynthesis where light energy is harnessed and converted into chemical energy. During these reactions, chlorophyll and other pigments in the thylakoid membranes of chloroplasts absorb sunlight. This energy drives the production of ATP (adenosine triphosphate) and NADPH (nicotinamide adenine dinucleotide phosphate), both of which are energy carriers used in the subsequent stages of photosynthesis and in various cellular processes.

These reactions also involve the splitting of water molecules, releasing oxygen as a byproduct. The energy captured as ATP and NADPH serves as the fuel for the later light-independent reactions, commonly known as the Calvin cycle, which utilizes this energy to fix carbon dioxide and synthesize glucose.

In contrast, the Calvin cycle and light-independent reactions occur after the initial absorption of light and do not directly involve the conversion of light energy into chemical energy. Glycolysis, on the other hand, is a metabolic pathway that breaks down glucose to extract energy and does not occur in the photosynthetic process.