Step 1: Understanding the Concept
Green plants trap light energy with chlorophyll and convert it into chemical energy stored in sugars.
Step 2: Process
This light-driven synthesis of food from carbon dioxide and water, with release of oxygen, is photosynthesis.
Step 3: Importance
It feeds the plant and, through food chains, almost all other organisms, and keeps oxygen in the atmosphere.
Final Answer:
Light is needed for photosynthesis.
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